Two solid spheres of different materials have the same moments of inertia about their diameters. If `r_(1)` and `r_(2)` are their radii, ratio of their densities is
A. `r_(1)^(3) : r_(2)^(3)`
B. `r_(2)^(3):r_(2)^(3)`
C. `r_(1)^(5):r_(2)^(5)`
D. `r_(2)^(5):r_(1)^(5)`