Fact 1: Magnetism can cause objects to repel each other.

Fact 2: Like magnet poles push away or repel each other.

Given the two facts above, answer the question "What can cause objects to push away each other?" with the following options: 
- work
 - mines
 - potential energy
 - heat energy
 - magnetism
 - electrically
 - friction
 - gravity


 

     magnetism    