Ans: B
$\begin{array}{rcl}
\dfrac{1}{2} \times \dfrac{4}{3} \pi r^3 & = & \pi r^2h \\
\dfrac{2}{3} r & = & h \\
\dfrac{r}{h} & = & \dfrac{3}{2} \\
r:h & = & 3 : 2
\end{array}$
$\begin{array}{rcl}
\dfrac{1}{2} \times \dfrac{4}{3} \pi r^3 & = & \pi r^2h \\
\dfrac{2}{3} r & = & h \\
\dfrac{r}{h} & = & \dfrac{3}{2} \\
r:h & = & 3 : 2
\end{array}$
