Match the radical expressions below with the letters labeling their equivalent exponential expressions.
1. $\sqrt[4]{17^3}$
2. $\sqrt[4]{a^3}$
3. $\frac{1}{\sqrt{17}}$
4. $\sqrt[3]{a^4}$
5. $\sqrt[3]{17^2}$

A. $17^{-1/2}$
B. $17^{3/4}$
C. $17^{2/3}$
D. $a^{3/4}$
E. $a^{4/3}$