Answer
See explanation.
Work Step by Step
The 2 spheres have opposite charges and attract, or one is positively charged and one is neutral, or one is negatively charged and one is neutral. In the latter two cases, the attraction occurs because of induced charge – see Figure 21.7b for the situation.
In any of these cases, the 2 conducting spheres will not cling together after touching. After they touch they will each have the same charge, or they will both be neutral. Zero charges have no effect on one another, and like charges repel.
