An Uncharged Spherical Conducting Shell Surrounds a Charge −Q at the Center

Multiple Choice

An uncharged spherical conducting shell surrounds a charge −q at the center of the shell. Then charge +3q is placed on the outside of the shell. When static equilibrium is reached, the charges on the inner and outer surfaces of the shell are respectively

A) +q, −q.
B) −q, +q.
C) +q, +2q.
D) +2q, +q.
E) +3q, 0.