Two Conducting Spherical Shells, a and B, Are Made of the Same

Multiple Choice

Two conducting spherical shells, A and B, are made of the same material, have radii r and 2r, and have initial charges of -Q. When sphere A is brought into a space free of other charges, the electric potential at a distance R > 2r from the center of the sphere is -V. Sphere A is removed, and sphere B is brought to the same point. The electric potential due to sphere B at a distance R from its center is

A) 2V.
B) V.
C) 0 V.
D) -V.
E) -2V.