Central Ideas and Details

CHAPTER FIVE · INFORMATION AND IDEAS

If a friend asks what a movie was about, you do not recite the plot scene by scene. You compress a two-hour film into one or two sentences that capture what actually mattered: who wanted what, what got in the way, how it ended. If that same friend instead asks what the villain said in one specific scene, a plot summary is useless; you need the exact line, from the exact moment, spoken by the exact character. Both are real answers to real questions about the same movie.

College Board calls this skill Central Ideas and Details. It sits inside the Information and Ideas part of the test. A question either asks for the passage’s central point, the equivalent of your one-sentence summary, or it asks for one specific fact the passage states, the equivalent of the villain’s exact line. The two tasks require different scopes of attention. A central-idea answer has to account for the passage as a whole, including any turn or limitation that materially changes its point. A detail answer has to match one exact fact, and nothing beyond it.

Know Whether the Question Asks for the Main Idea or a Detail

Read this passage once and hold both tasks in mind at the same time.

Sea otters eat sea urchins, and urchins graze kelp. Hunters cleared the otters from the northern coast during the nineteenth century, urchin numbers climbed, and the kelp forests thinned to bare rock. Otters returned to several bays after 1970, and kelp cover in those bays now matches the old surveys.

Ask for the central idea, and the answer has to cover all three sentences: the passage links the loss and return of otters to the collapse and recovery of the kelp forests. Ask instead when the otters came back, and the answer shrinks to a single year, with the rest of the passage set aside entirely while you answer.

Both answers come from the exact same words. The stem alone determines whether your answer has to cover the whole passage or one stated detail. Reading the stem first is a useful way to fix whether the task is main idea or detail before close reading.

State the Central Idea Briefly

After reading, ask which single statement best captures the passage as a whole, and say that statement to yourself before you look at a single answer choice. The claim can arrive anywhere in a passage. Some passages state it in the opening sentence and spend the rest supporting it. Others build toward it gradually and only state it at the close.

Apply that to the otters passage. Taken as a whole, it links the removal of one predator to the collapse of the kelp forests, and that predator’s return to the forests’ recovery. The opening sentence about urchins grazing kelp is background the reader needs in order to follow that claim; background is identified by the role it plays, not by how early it appears. Ask what each sentence is actually there to do: supply a condition the reader needs in order to follow the claim, or state and develop the claim the passage exists to make.

Stating the main idea in one sentence. State the central idea as briefly as you can without dropping a part of the passage you actually need. A prediction that keeps running long usually means you are still summarizing sentence by sentence instead of naming what the passage as a whole establishes. On a passage built as a view revised, the shape covered in the Text Structure and Purpose chapter, asking what changed by the end is a fast route to the same statement.

Build the Central Idea From the Whole Passage

Sometimes one sentence carries the whole central claim outright. Other times the claim has to be assembled from two separate parts, most often a finding together with the limit or result attached to it. The shapes named in the Text Structure and Purpose chapter tell you which situation you are in and exactly where to look first.

Signal words flag places to look, not answers to give. However, but, and in fact mark a turn. Reporting verbs such as researchers found mark new material arriving. Either kind of signal can introduce the central claim itself, or it can just as easily introduce evidence for a claim stated elsewhere. Treat every signal as a place worth a second look, not as the answer by itself. Whatever you finally select still has to cover the passage from its first sentence to its last.

Keep the Answer Within the Passage’s Scope

Wrong answers on main-idea questions rarely change the subject entirely. They change the size or the shape of the claim while staying on-topic, which is exactly what makes them tempting. A choice that fails on any single dimension below fails completely, no matter how well it otherwise matches the passage’s subject.

A passage about otters in several northern bays supports a claim about those otters in those bays, not about otters everywhere or predators in general: that is population. A passage covering a stated period supports a claim about that period, not one using always, historically, or from now on: that is time. A passage about one coast supports a claim about that coast, not coastlines worldwide: that is place. A passage about kelp forests supports a claim about kelp forests, not marine ecosystems as a whole category: that is category. A passage stating a cause the author suggests supports a claim at that same strength, not the sole cause or a proven one: that is strength. A passage attributing a claim to researchers, critics, or editors supports a claim owned by those people, not the same claim presented as the passage’s own settled position: that is attribution. A passage describing a comparison running one way supports that same direction, not the comparison reversed or a ranking flipped: that is direction. A passage reporting an association supports a claim at the level of association, not a cause promoted from it. If the passage itself explicitly attributes a cause, a main-idea answer should preserve that attribution unless the passage later qualifies it; do not automatically rewrite the author’s causal claim as mere association: that is causal status.

Do not answer the lesson you expected instead of the one the passage gives. Some topics carry an obvious lesson before the passage has said anything at all. Environmental damage invites “the project failed.” A reform story invites “people finally listened to the evidence.” A scientific correction invites “the old theory was useless.” The passage in front of you may be written specifically to deny that expected lesson. Before choosing an answer, ask whether it comes from the text itself or from the story you expected this topic to tell. A choice can be sensible, important, and even historically accurate elsewhere, and still fail here if this particular passage reached a different point.

Find the Detail and Check Its Context

A detail question hands you a specific target. Locate the sentence that holds it and answer from there, then read one sentence on either side whenever the answer depends on a pronoun, a date, or who is actually speaking. Most losses on this question form come from answering with a neighboring fact that happens to be perfectly true.

Do not choose by matching words alone. A choice can repeat the passage’s own language and still attach it to the wrong person, the wrong time, or the wrong claim, which is a reliable way to lose a question you had genuinely understood.

The Chicago Defender traveled south in the hands of Pullman porters, who carried bundles aboard and left them at stations along the line. Copies passed from reader to reader, and a single issue might be read aloud to a whole room. Editors reckoned four or five readers for every copy sold.

If the question asks how the paper reached the South, go to sentence one: porters carried it aboard trains and left it at stations. If the question asks what happened to a copy after it arrived, go to sentence two: it moved between readers and was read aloud to groups. If the question asks what the editors estimated, go to sentence three: four or five readers for every copy sold.

Notice that the third answer belongs to the editors, not to the passage itself. A reported estimate keeps its owner. A choice that presents that figure as a measured circulation number has changed who is speaking without announcing it, even while using the passage’s own numbers.

Apply the Same Method to Narrative Passages

Literature passages worry students more than they should, because the two underlying questions never actually change. A central idea in a narrative summarizes the situation the passage presents or the change it records, and it may concern a relationship, a conflict, a narrator’s attitude, or a tension the passage leaves deliberately unresolved. A narrative answer may describe an implied attitude or tension when the text genuinely supports it, and it must never supply a feeling, a motive, or a theme that the actions and language on the page do not actually justify. A detail, in a narrative exactly as in an expository passage, is simply what somebody did, said, or noticed.

For eleven years Mr. Oyelaran had unlocked the shop at six. He unlocked it at six on the morning after the funeral as well, and stood behind the counter in the dark until the first customer knocked.

Nothing here states grief, and nothing announces a theme. The passage reports a habit, then reports that habit surviving a death. What the passage actually supports is that a man held to his routine on the morning after a funeral, with the routine deliberately placed beside the death for the reader to notice. A choice that names his feelings goes beyond the evidence. A choice reporting only that he owns a shop stops well short of it.

Worked Examples for Main Ideas and Details

Combine Both Parts of the Central Idea

Portable sundials survive in some number from the sixteenth century, and museums have long catalogued them as instruments for travelers. A researcher has measured the hour lines on forty of them and finds that most are cut for a single latitude. A dial calibrated for one city misreads the hour by twenty minutes a day’s ride away.

Which choice best states the main idea of the text?

A. A researcher measured the hour lines on forty surviving portable sundials

B. Most surviving portable sundials are cut for one latitude, which creates tension with their catalogue description as travelers’ instruments

C. Sixteenth-century sundials were less accurate than the clocks that replaced them

D. Portable sundials were never intended for use away from home

No single sentence carries this passage on its own. The measurement in sentence two and the consequence in sentence three together bear on the catalogue description in sentence one, and the central idea has to hold all three at once. That is B. A is true, and it reports only the method rather than what the method actually showed; it covers one sentence out of three. C invents a comparison to clocks that never appears anywhere in the passage. D is the closest wrong choice, and it settles a question the passage deliberately leaves open; a measurement about calibration is not the same as a claim about original intention.

Locate a Historical Detail

The Chicago Defender traveled south in the hands of Pullman porters, who carried bundles aboard and left them at stations along the line. Copies passed from reader to reader, and a single issue might be read aloud to a whole room. Editors reckoned four or five readers for every copy sold.

According to the text, how did the Defender reach readers in the South?

A. Porters carried copies aboard trains and left them at stations

B. Editors mailed copies directly to southern subscribers

C. Local printers in the South reproduced each issue

D. Readers copied articles by hand and passed them along

A restates sentence one without repeating its exact wording, which is the delivery method the passage actually describes. B assigns an action, mailing, to editors, who appear in sentence three doing arithmetic instead. C invents printing activity that no sentence in the passage describes. D reverses what sentence two actually reports: copies passed between readers, and nobody in the passage copies anything by hand.

Choose the Reading the Text Supports

For eleven years Mr. Oyelaran had unlocked the shop at six. He unlocked it at six on the morning after the funeral as well, took the till from the safe, and counted it twice before the first customer knocked.

Which choice best states the main idea of the text?

A. A man keeps to a long-standing routine on the morning after a death

B. A man is too distracted by grief to complete his usual work

C. A man finds comfort in the ordinary tasks of his shop

D. A shopkeeper opens earlier than his customers expect

Choices B and C each offer a reading of the counting, and both are exactly the kind of reading a thoughtful reader is tempted to supply. The passage itself only reports the actions and stops there, which makes A the answer: eleven years of habit, the same hour on a hard morning, and the usual work completed regardless. B reads a state of mind, distraction, out of a repeated action that could just as easily show care; either way, the work still gets done. C supplies comfort that the narration never states; it is the warmer reading of the identical evidence, and the passage reports no comfort and no relief. D needs a view of customer expectations the passage never reports.

When two choices assign different emotions to the same action, ask whether the passage actually gives evidence that distinguishes between them. If it does not, the choice that stays at the level the text genuinely supports is the one to prefer, however reasonable the more specific reading feels.

Separate Missing Measurement From Measured Results

Across trials at two sites, the treatment reduced crop loss by 71 percent among mature plants. Its effect on seedlings could not be measured, because too few seedlings were affected by the pest during the trial period.

Based on the text, what is true about the treatment’s effect on seedlings?

A. The effect was smaller than the effect in mature plants

B. The trial produced no measurement of it

C. The effect matched the effect in mature plants

D. The treatment offered seedlings no protection

B is the answer: too few affected seedlings left the question open, which is exactly what the passage reports. A requires a comparison between two numbers, and the passage supplies only one. C claims equality, and equality is itself a finding, one this trial never produced. D is the most tempting error on the page: silence about protection is not evidence against it.

No evidence of an effect is not evidence of no effect. A passage reporting that something could not be measured has told you a fact about the study, not a fact about the world, and choice D above fails on exactly that distinction. A failure to detect a clear effect can still narrow which effect sizes remain plausible when a study is precise enough, and even then it does not by itself show that the true effect is zero. Here the passage is simpler than that: too few seedlings were affected by the pest for any effect to be measured at all.

Track the Shift From Opening View to Final Point

A passage can open with what people once believed and spend the rest of its length revising that belief. An answer that simply repeats the opening view has summarized sentence one and missed the reason the passage exists.

For decades, marine biologists believed a certain deep-dwelling squid species was solitary, rarely seen because it actively avoided others of its own kind. Individuals tagged and tracked since 2015 gather in loose groups near seasonal feeding grounds, dispersing again once the food is gone.

Which choice best states the main idea of the text?

A. This squid species is a solitary, deep-dwelling animal

B. This squid species forms temporary groups around seasonal food, unlike the earlier belief that it was solitary

C. Tagging technology has improved since 2015

D. This squid species is difficult to observe in the deep ocean

B captures the revision itself, the actual reason this passage exists. A repeats only the opening belief the tracking data goes on to overturn. C mistakes a detail supporting the finding for the finding itself. D is true in general and answers nothing this specific passage claims.

Follow the Passage to Its Main Point

Some subjects carry an expected moral before a single sentence of the passage has been read. A passage can be written specifically to deny that expected moral.

A century-old dam, long blamed for the decline of the river’s native fish, was removed in 2019. Fish counts the following year showed no measurable increase, and biologists now suspect a downstream water-treatment plant, built the same decade as the dam, was the larger obstacle all along.

Which choice best states the main idea of the text?

A. Removing the dam restored the river’s native fish population

B. Removing the dam did not produce the expected recovery, pointing to a different likely cause

C. The dam should never have been built

D. Water-treatment plants always harm fish populations

A is the lesson the setup seems to promise, a blamed dam removed should obviously help, and the passage’s second sentence directly denies it. B is what the passage actually reports. C invents a judgment about the dam’s original construction that the passage never makes. D expands one suspected case into a universal claim about an entire category of infrastructure.

Match the Answer’s Strength to the Passage

May contribute is not causes. Often is not always. A choice can upgrade the force of a claim the passage stated far more cautiously, without ever announcing the upgrade.

Researchers note that reduced sunlight exposure may contribute to slower growth in a group of greenhouse plants, though other factors such as soil composition and watering frequency were not controlled for.

Which choice best states what the passage claims about sunlight exposure and plant growth?

A. Reduced sunlight causes slower growth

B. Reduced sunlight may contribute to slower growth, though the study leaves other factors unaccounted for

C. Reduced sunlight has no effect on growth

D. Slower growth always follows reduced sunlight

B matches the passage’s own hedged wording exactly. A upgrades may contribute to causes, a stronger claim the uncontrolled factors do not support. C reverses the finding entirely. D upgrades a partial, uncertain contribution into an absolute, universal rule.

Keep Comparison Direction Straight

A choice can quote the right two groups and still reverse what was actually being compared between them.

Group A, which received the standard treatment, ended the trial with the higher average recovery score. Group B, which received the experimental treatment, started lower but posted the larger improvement over the course of the trial.

Which choice accurately describes the comparison between the two groups?

A. Group B ended the trial with a higher score than Group A

B. Group A ended higher, while Group B improved more over the course of the trial

C. Group A improved more over the course of the trial than Group B did

D. Both groups ended the trial with identical scores

B keeps both halves of the comparison in their correct direction. A reverses the final standing between the two groups. C reverses which group actually improved more; that distinction belongs to Group B. D invents an equality neither sentence reports.

Attach Dates to the Correct Event

A date can belong to a study, an expedition, a publication, or a rediscovery. Reusing a correct-sounding date does not guarantee it still refers to the same event the question is actually asking about.

Dr. Petrova’s field notes, compiled during her 1987 expedition, were not published until a colleague rediscovered them in a university archive in 2016.

According to the text, when did Dr. Petrova conduct her expedition?

A. 1987

B. 2016

C. Sometime between 1987 and 2016

D. The passage does not say

A is the year attached specifically to the expedition itself. B correctly names a year in the passage, and attaches it to the wrong event, the rediscovery rather than the expedition. C invents a range the passage never suggests, since both years are stated exactly. D is simply false; the passage states the expedition’s date directly.

Match the Answer to the Passage’s Evidence Level

Refusing to invent a feeling the passage never earns is the right instinct, and it should stay the right instinct. But that caution can tip into a different mistake: treating every implied characterization as an overreach, even when the language genuinely narrows the reading to one answer. Three useful evidence levels help separate warranted characterization from unsupported interpretation.

At the first level, the passage states the fact, feeling, or judgment directly. At the second level, nothing is stated outright, but multiple details converge, tone, contrast, word choice, so tightly that only one reading survives; this level is fully testable, and a correct answer can live here. At the third level, the behavior is compatible with several different motives or feelings, and the passage never narrows among them; this level stays off-limits no matter how natural one particular reading feels.

The important distinction is whether the passage itself narrows the interpretation or the reader supplies the narrowing. It is not about how confident a reading feels.

A committee praised the senator’s decades of dedicated public service before declining, without further comment, to renew his subcommittee assignment.

Which choice best describes what this sentence most strongly suggests about the committee’s actual view of the senator?

A. The committee valued his experience above all other considerations

B. The committee’s stated praise and its actual decision point in different directions

C. The committee disapproved of his earlier policy positions

D. The committee planned to replace him with a younger member

The praise and the quiet decline of an assignment sit right next to each other, and that placement is the sentence’s own doing, not an outside assumption. Warm language followed immediately by a diminished role is a specific, narrow pattern: the words say one thing, and the action says another. That makes B the strongest supported reading: the praise and the decision point in different directions without establishing why. A takes the praise at face value and ignores what the committee actually did. C and D both name a specific cause the sentence never supplies; the sentence supports a gap between statement and action, not a reason for that gap.

A tester repeatedly opened the manual to the same worn page before every attempt, though she had long since memorized its contents.

Which choice best describes what this detail most strongly suggests?

A. The tester had forgotten how to perform the procedure

B. The manual contained a step not present in her memory

C. The tester continues a familiar checking routine even though she no longer needs the page for information

D. The tester distrusted her colleagues’ training methods

Memorizing the manual and still returning to the same page before every attempt is a specific, converging pattern: the behavior does not fit forgetting, since she has the contents memorized, and it does not fit distrust of anyone else, since nothing points outward. What the passage actually supports is the behavior itself, a checking routine that has outlived the need for it, without the passage narrowing down why she keeps doing it. That is C. A directly contradicts the stated fact that she had memorized the manual. B invents content the sentence never mentions. D introduces other people the passage never names.

Include Both the Surprise and Its Explanation

Several main-idea shapes are already familiar: a view revised, a claim with its evidence, two positions compared. One more shape shows up often enough in science and social-science passages to deserve its own name. The passage opens with a result that looks backward or unexpected, then spends the rest of its length explaining the mechanism that makes the surprising result make sense after all.

The central idea in this shape is not the surprising result alone, and it is not the mechanism alone. It is the pairing: this looked odd, and here is why it actually was not.

Cities that invested heavily in new public transit lines saw average commute times rise, not fall, over the following decade. Ridership data offer an explanation for the pattern: the new lines attracted riders who had previously avoided commuting altogether, drawn by an option that finally made a longer trip worthwhile, and their added trips outweighed the time saved by former drivers who switched to transit.

Which choice best states the main idea of the text?

A. New transit investment in cities was largely unsuccessful

B. Rising commute times occurred because former drivers switched to transit

C. Commute times rose despite new transit investment because the new option drew in riders who had not previously commuted at all

D. Cities should not invest in public transit if commute times matter

An answer that reports only the rising commute times leaves out why that outcome, surprising given the investment, actually happened. An answer that reports only the mechanism leaves out the very tension the passage sets up in its first sentence. Only a choice holding both together earns credit, which is C. A overstates a broad failure the passage never claims. B names the wrong mechanism; the passage credits new riders, not switched drivers, for the change. D draws a policy conclusion the passage never reaches.

Use a Small Inference to Resolve a Detail

Most detail questions resolve by locating a sentence and reading it closely. A smaller set asks what a text best supports, and the supported statement is not sitting in any single sentence. The supported statement may require a short inference, but every part of it must remain anchored to facts the passage supplies.

Restoration records for the cathedral’s east wing survive in continuous detail from 1680 onward. No comparable records exist for the west wing before 1750, though architectural evidence confirms the west wing was already standing by 1680.

Which statement is best supported by the text?

A. The west wing was built using different materials than the east wing

B. The surviving documentation for the west wing is less complete than for the east wing during this period

C. The west wing suffered more damage than the east wing during this period

D. Restoration work on the west wing did not begin until 1750

Nothing states a reason for the missing records directly. But a wing confirmed to exist since 1680, with no records until 1750, sitting beside a second wing whose records run continuously across the same span, points to exactly one supported conclusion: whatever the cause, less documentation survives for the west wing across that period. That is B, a single step from the gap the passage establishes, and it stops at the gap itself rather than explaining it. A, C, and D each name a specific cause, materials, damage, or a construction delay, that the passage supplies no basis for at all.

Use This Method

1. Read the stem and identify the task: the passage as a whole, or one stated fact.

2. Read the whole passage. Turn words and reporting verbs mark places worth attention, not the answer itself.

3. For a central idea, state the smallest claim that still covers the whole passage before you look at the choices.

4. For a detail, locate the exact target and read enough of the surrounding sentences to settle any pronoun, date, or speaker the answer depends on.

5. Check the surviving choice against scope, attribution, direction, causal status, and strength before you select it.

Quick Review of Hard Cases

Each of these was taught earlier with a full worked example. Here, each gets its own compact illustration, so this list teaches on its own rather than just pointing back.

A true detail is too small for the whole passage. The researcher’s measurement of forty sundials is real and accurate, and it covers only one sentence of three; the central idea needs the catalogue claim and the twenty-minute consequence as well.

The opening belief is not the final point. A squid species believed solitary for decades turns out to gather around seasonal food; a choice that only restates the old belief has summarized sentence one and missed why the passage exists.

The finding is not the method. Researchers may survey, measure, or tag; when a passage emphasizes what that work revealed, an answer that stops at what they did is one level too small, the way “a researcher measured hour lines” stops short of what the measurement showed.

The main idea may need two parts. A result plus its limitation, or a finding plus the earlier belief it changes, sometimes has to appear together in a single answer; one half can be accurate and still leave the claim incomplete.

The passage never states one single topic sentence. Short passages can build their point across several sentences at once, the way the sundial passage needs its catalogue claim, its measurement, and its consequence all held together, with no single sentence carrying the whole idea alone.

A reasonable lesson is not the passage’s lesson. A dam removed after decades of blame seems to promise recovery; this passage instead reports no measurable increase and points to a different cause, denying the lesson the setup seems to promise.

The choice makes the passage bigger than it is. One valley’s aerial survey supports a claim about that valley, not about Roman roads across the entire empire, even though the revision itself, a network rather than one road, survives the wider claim.

The choice makes the passage stronger than it is. May contribute is not causes, and often is not always; a passage hedging its own claim does not earn a choice that states that claim with more confidence than the author risked.

The choice adds an intention. A sundial calibrated for one city does not prove it was never meant to travel; a measurement about calibration is a different claim from one about original purpose.

The choice adds an emotion. Counting the till twice can show hesitation, care, distraction, or habit equally well; unless the passage actually distinguishes among them, naming one specific feeling goes beyond what the actions support.

A missing measurement is turned into a result. A trial that could not measure an effect in seedlings has told you about the trial, not about the treatment; “no measurement” and “no effect” are different findings entirely.

A comparison is reversed. Group A can finish higher while Group B improves more; a choice can name the correct two groups and still swap which one did which.

A detail answer uses the right words on the wrong person. Editors estimated four or five readers per copy; that estimate stays with the editors and never becomes a measured circulation figure just because a choice reuses the number.

A detail answer uses the right fact from the wrong sentence. A passage can report both how the paper reached the South and what happened once it arrived; only one of those sentences answers a stem asking specifically about delivery.

A date attaches to the wrong event. An expedition dated 1987 and a rediscovery dated 2016 are two different events in the same passage; reusing either year for the other question misreports what actually happened when.

A two-part detail answer is half right. Cards that reach a lectern and then go unused are two separate facts in one answer; a choice can get the first half right and reverse the second, or the reverse, and still fail as a whole.

Compare Levels of Evidence and Certainty

These pairs sit beside each other in a close reading of the same passage. The sentence you are reading always decides which side of each pair it can actually support.

Practice

Answers and Explanations

Final Checks Before You Answer

When two choices still look possible, the miss is usually small: a choice that is completely true and still too narrow, a choice that covers almost everything and misses one final turn, or a choice that upgrades certainty the passage never claimed. Each check below comes with its own worked item.

A choice can fail in three related ways even when it uses accurate language: by being true of only one sentence, by covering most of the passage but missing its final turn, or by simply repeating the opening view a passage goes on to revise.

For years, urban planners assumed rising rents in the district were driven mainly by an influx of remote workers relocating from more expensive cities. A 2023 zoning review instead found that a decade-long reduction in new housing permits, unrelated to remote work, better explains the increase, though it also identified remote-worker demand as a real, secondary factor in the final two years.

Which choice best states the main idea of the text?

A. Remote workers relocating to the district drove up rents

B. A decade-long drop in housing permits better explains rising rents than the remote-worker theory, though remote work played a real secondary role in recent years

C. A decade-long drop in housing permits better explains rising rents than the remote-worker theory

D. A 2023 zoning review examined housing permits in the district

B is the only choice that survives all three checks: it is not the discarded opening belief, and it does not stop short of the passage’s final turn. A simply repeats the view the zoning review revises. C covers the revision but drops the final clause restoring remote work as a real, secondary factor, which is exactly the kind of missed ending that makes an otherwise strong choice incomplete. D is completely true and covers only the method, one sentence out of three.

A choice can name the method, name the finding, or merely give the topic, and only the choice that reaches all the way to what the finding actually changes is complete.

To determine whether coral transplantation could restore damaged reef sections, researchers attached lab-grown coral fragments to twelve degraded sites and monitored growth for three years. Eight of the twelve sites showed coral cover comparable to undamaged reef nearby, while four showed almost no growth, and follow-up analysis linked the failures to persistently warmer water at those specific sites.

Which choice best states the main idea of the text?

A. Researchers attached lab-grown coral fragments to twelve degraded reef sites

B. Coral transplantation restored reef cover at most sites, with warmer water explaining the sites where it failed

C. Coral transplantation restored reef cover at most sites

D. The passage is about coral reef restoration

B reaches the finding and what that finding’s exceptions turn out to mean. A names only the method. C names the finding and stops before the explanation for the failures, the detail that gives the finding its full shape. D gives a topic, not a claim; it never says what the passage actually establishes about that topic.

A choice can feel important or sound insightful without being supported, and unstated judgment is exactly what separates the two.

The committee’s final report recommended extending the review period by six months, citing incomplete data from two of the five regions surveyed.

Which choice best states what the report recommends and why?

A. The committee recognized the review process was fundamentally flawed and needed to be redesigned

B. The committee recommended a six-month extension because data from two of five regions was incomplete

C. The committee felt pressured by incomplete data to delay their findings

D. The committee’s recommendation reflects a broader crisis in data collection standards

B states exactly what the passage reports, no more. A sounds like a serious, insightful reading and requires a judgment about the whole process that the passage never makes. C invents a feeling, pressure, behind a decision the passage reports as a straightforward recommendation. D inflates one specific data gap into a sweeping claim about a “crisis,” which feels important and is entirely unsupported.

A choice can preserve every noun in the passage and still change the claim by altering a verb or slipping in an absolute word like all, always, or entirely, and it can also expand the group a finding actually covers.

Several coastal towns in the survey reported improved water quality after new filtration systems were installed, though the towns without new systems showed no consistent change.

Which choice best states what the passage supports?

A. All coastal towns showed improved water quality after installing new filtration systems

B. Several coastal towns in the survey saw improved water quality after installing new filtration systems

C. Every town with a new filtration system reported dramatically better water quality

D. Coastal towns worldwide benefit from new filtration systems

B matches the passage’s own word, several, and its own claim exactly. A smuggles in all, which the passage’s own “several” rules out. C keeps every noun from the passage and inflates the verb into dramatically better, a strength the passage never states. D expands a survey of specific coastal towns into a worldwide claim.

A choice can claim causation where the passage only reports an association, and separately, it can claim proof or disproof where the passage only supports, questions, or complicates.

Regions with higher rates of home gardening also reported lower rates of reported food insecurity during the same survey period, though researchers noted several other regional factors were not controlled for.

Which choice best states what the passage supports?

A. Home gardening causes lower food insecurity

B. Higher rates of home gardening were associated with lower reported food insecurity during the same period, though other factors were not ruled out

C. The survey proves that gardening reduces food insecurity

D. Home gardening has no relationship to food insecurity

B stays at the level of association the passage actually reports, hedge included. A upgrades that association to causes. C claims the passage proves something it only associates. D contradicts the reported relationship entirely.

A choice can supply a motive the passage never states, and separately, it can name a specific feeling when the text supports only the behavior itself.

Every evening that week, Mr. Duarte watered the neighbor’s wilting garden before his own, though the neighbor had moved away in the spring.

Which choice best states what the passage supports about Mr. Duarte?

A. Mr. Duarte missed his neighbor and watered the garden out of loneliness

B. Mr. Duarte watered the neighbor’s garden before his own each evening that week

C. Mr. Duarte watered the garden because he believed the neighbor would return

D. Mr. Duarte was angry that his neighbor had moved away

B reports only the behavior the passage actually gives. A names a specific feeling, loneliness, with nothing in the text to distinguish it from care, habit, or any number of other explanations. C supplies a motive, a belief about return, that the passage never states. D invents a feeling opposite to A with equally little support; when two answers can invent opposite emotions from the same behavior, neither one is earned.

A passage that says an effect could not be measured supports a statement about the missing measurement, never a guess about what the effect actually was.

The survey could not determine whether remote employees changed their commuting habits, since too few respondents in that category answered the relevant question.

Based on the text, what is true about remote employees’ commuting habits?

A. Remote employees did not change their commuting habits

B. The survey produced no measurement of any change

C. Remote employees changed their commuting habits significantly

D. Commuting habits are unrelated to remote work

B matches exactly what the passage reports: an absence of measurement, not a result. A and C both convert that absence into an actual finding, in opposite directions. D invents a relationship claim the passage never makes in either direction.

A detail question sends you to one exact sentence, and when a pronoun sits inside that sentence, the surrounding context is what tells you exactly what it refers to.

The city’s first bike-share program launched in 2015 with two hundred bicycles. It struggled with theft in its early months, and organizers relocated its docking stations twice before ridership stabilized.

According to the text, what struggled with theft in its early months?

A. The bike-share program

B. The two hundred bicycles

C. The docking stations

D. The city government

A is correct: it in the second sentence refers back to the program named in the first sentence, not to the bicycles or the docking stations that appear later in that same sentence. B and C both grab a nearby noun that sits closer to the pronoun on the page but is not what the pronoun actually refers to. D is not mentioned in this passage at all.

A number in a passage keeps its exact unit, period, and group, and reusing the number for a different one of those is a common way to misstate a detail.

The clinic recorded 340 patient visits in March 2022, up from 210 in the same month the previous year, an increase researchers attributed to a new walk-in policy introduced that January.

According to the text, what does the number 340 refer to?

A. Patient visits in March 2022

B. Patient visits in March of the previous year

C. The total number of walk-in policies introduced

D. The percentage increase in visits

A keeps the number attached to its exact period, March 2022. B attaches the same kind of figure to the wrong year; 210 belongs to the previous year, not 340. C and D both invent a category, a count of policies and a percentage, that the number was never measuring in the first place.

A date in a passage stays attached to the specific event it actually dates, and a nearby event does not inherit it just because both appear in the same sentence.

The university acquired the manuscript in 2021, though scholars date its actual composition to sometime in the early 1400s based on the paper’s watermark.

According to the text, what does the year 2021 refer to?

A. When the university acquired the manuscript

B. When the manuscript was composed

C. When the watermark was first identified

D. When the paper was manufactured

A is the event 2021 actually dates. B attaches that date to composition, which the passage places in the early 1400s instead. C and D both invent events the passage never dates at all.

When an answer makes two separate claims, both of them have to be correct; one accurate clause never rescues an invented one.

The board reviewed the proposal in March and approved a revised version in May, after requesting changes to the budget section only.

Which choice accurately describes the board’s actions?

A. The board reviewed the proposal in March and approved the original version in May

B. The board reviewed the proposal in March and approved a revised version in May

C. The board rejected the proposal in March and approved a revised version in May

D. The board reviewed the proposal in May and approved a revised version in March

B is the only choice where both clauses hold. A gets the first clause right and the second wrong; the approved version was revised, not original. C gets the second clause right and the first wrong; the board reviewed the proposal in March, it did not reject it. D reverses both months entirely.

A correct answer is allowed to paraphrase the passage rather than copy its exact words, and it should be judged on whether the meaning matches, not on how many words overlap.

The recipe calls for the dough to rest for two hours before shaping.

According to the text, what should happen to the dough before shaping?

A. It should sit undisturbed for two hours

B. It should be kneaded for two hours

C. It should rise overnight

D. It should be refrigerated for two hours

A paraphrases rest as sit undisturbed, which shares no exact wording with the passage and still means exactly the same thing. B, C, and D all use different, plausible-sounding kitchen actions that the passage does not actually describe; none of them can be excused for reusing the passage’s own vocabulary, because none of them do.

When two choices both seem genuinely supported, prefer the one that needs fewer added assumptions and still covers the scope the question actually asked for, since the passage’s own stated limits are usually the detail that separates them.

A regional survey found that towns adopting curbside composting saw a measurable drop in landfill waste within one year. The survey also noted that towns with the largest drops had run public awareness campaigns alongside the composting rollout, though the survey could not separate the effect of the campaigns from the effect of composting itself.

Which choice best states the main idea of the text?

A. Curbside composting reduced landfill waste in towns that adopted it, though the role of accompanying awareness campaigns could not be separated from composting’s own effect

B. Public awareness campaigns were the primary reason landfill waste dropped in towns that adopted composting

C. Landfill waste increased in towns without composting programs

D. All towns that adopted composting ran public awareness campaigns

Both A and B can look supported at a glance, since both facts, composting and campaigns, appear together in the passage. The passage itself supplies the detail that separates them: it explicitly says the two effects “could not be separated.” A preserves that exact uncertainty. B resolves it in one direction with no support for doing so; naming campaigns as the primary reason is an assumption the passage explicitly declines to make. C invents a finding about towns without composting that the passage never reports. D turns “towns with the largest drops” into every town that adopted composting at all.