A student rubs a rubber rod with fur, producing a negative charge on the rod. The student then touches the rod to a hollow, neutral metal sphere that stands on an insulating plastic stand. This transfers negative charges from the rod to the sphere: Which statement best predicts what will happen to the charge, and why?

A It will distribute itself evenly over the surface of the sphere, because like charges repel and the sphere is a conductor.

B It will remain at the point of contact between the rod and the sphere, because resistance in the metal prevents the charges from easily moving.

C It will slowly drift to the bottom of the sphere, because the charges rapidly attach to individual atoms, making them slightly heavier than surrounding atoms.

D It will quickly spread to the air around the sphere, because it will seek to occupy as large a volume of neutral matter as possible.