Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

Using the Power Rule of the laws of exponents which is given by $\left( x^m \right)^p=x^{mp},$ then \begin{array}{l}\require{cancel} \left( x^{1/5} \right)^{5/2} \\\\= x^{\frac{1}{5}\cdot\frac{5}{2}} \\\\= x^{\frac{1}{2}} \\\\= x^{1/2} .\end{array} Hence, $\text{ Choice D .}$