Find the Mass of a Spherical Surface Whose Density Is $\pi$

Multiple Choice

Find the mass of a spherical surface whose density is equal to the distance from a fixed diametral plane.

A) 5 $\pi$ a³
B) 4 $\pi$ a³
C) 3 $\pi$ a³
D) 2 $\pi$ a³
E) $\pi$ a³