Volumes of two spheres are in the ratio $2:3$, what can be the ratio of their radii ?

Question

$\begin{array}{1 1} (a)\; 3:\sqrt{2} \\ (b)\; \sqrt{3}:\sqrt{2} \\ (c)\; 3\sqrt{3}:3\sqrt{2} \\ (d)\; 9:4 \end{array}$