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

Fact 2: An object is a real-world thing.

Given the two facts above, answer the question "Magnetism can cause what to repel each other?" with the following options: 
- electromagnetic energy
 - flow of electrons
 - Veins and arteries.
 - barnacles
 - solid, liquid, gas
 - an electron lens
 - real-world things
 - Electrical energy


 

       real-world things  