Fact 1: When metal conducts heat , that metal expands.

Fact 2: Conduction is the passing of heat through a medium.

Given the two facts above, answer the question "What happens to metal when heat passes through it?" with the following options: 
- It sheds a layer of rust
 - kinetic energy
 - It expands
 - It turns into gold
 - electricity
 - mechanical
 - sweating
 - It contracts


 

   It expands      