Two solid spheres (A and B) are made of metals of different densities $p_A$ and $p_B$ respectively. If their masses are equal, the ratio of their moments of inertia $(I_B / I_A)$ about their respective diameter is

Question

\[\begin {array} {1 1} (a)\;\bigg(\frac{p_B}{p_A}\bigg)^{2/3} & \quad (b)\;\bigg(\frac{p_A}{p_B}\bigg)^{2/3} \\ (c)\;\frac{p_A}{p_B} & \quad (d)\;\frac{p_B}{p_A} \end {array}\]