Fact 1: Fanning a fire increases the oxygen near the fire.

Fact 2: Fire needs oxygen in the air to keep burning.

Given the two facts above, answer the question "What keeps a fire burning?" with the following options: 
- fanning it
 - energy
 - rain
 - smoke
 - sparks
 - evaporation
 - kinetic energy
 - heat energy


 

 fanning it        