A parabola crosses the x-axis at x = -1 and x = 5, and has a y-intercept of -5. Which equation represents this parabola?

A parabola with zeros at $-1$ and $5$ has the form $f(x)=a(x+1)(x-5)$. The $y$-intercept is $f(0)=a(1)(-5)=-5a=-5$, so $a=1$. Expanding, $f(x)=x^2-4x-5$, choice A. Choice B ($x^2+4x-5$) has zeros at $-5$ and $1$. Choice C ($x^2-4x+5$) has a $y$-intercept of $5$ and no real zeros. Choice D ($2x^2-4x-5$) has the right $y$-intercept but $f(-1)=2+4-5=1\ne0$, so $-1$ is not a zero. A candidate must match both the zeros and the intercept. Expanding $(x+1)(x-5)$ confirms the middle term is $-4x$.