Imagine That We Have Two Identical Metal Spheres on Insulating $\boldsymbol{\sigma}$

Imagine that we have two identical metal spheres on insulating stands that we give the same negative charge. If we slowly bring the spheres closer and closer together, the charge per unit area $\boldsymbol{\sigma}$ on each sphere will at the point nearest the other sphere

A) become increasingly negative.
B) become less negative.
C) remain constant.