Simplify: (a³/4)^4/3 for a > 0.

Use the power-of-a-power rule, $(a^m)^n = a^{mn}$, so the exponents multiply: $\frac{3}{4}\cdot\frac{4}{3} = 1$. The expression equals $a^1 = a$, which is choice D. Because the two fractions are reciprocals, they cancel completely. Choice A divides the exponents ($\frac{4}{3}\div\frac{3}{4}=\frac{16}{9}$) instead of multiplying them. Choice C subtracts them ($\frac{4}{3}-\frac{3}{4}=\frac{7}{12}$), which is the rule for dividing powers with the same base, not for raising a power to a power. Choice B matches no exponent rule at all; multiplying reciprocals can never leave $\frac{1}{3}$ behind, so it is only a plausible-looking distractor.