AMC 10 2008b Problem 3

Assume that $x$ is a positive real number. Which is equivalent to $\sqrt[3]{x\sqrt{x}}$? $\mathrm{(A)}\ x^{1/6} \mathrm{(B)}\ x^{1/4} \mathrm{(C)}\ x^{3/8} \mathrm{(D)}\ x^{1/2} \mathrm{(E)}\ x$