Fact 1: Coal is used to produce electricity by burning in coal-fire power stations.

Fact 2: Electricity is really the movement of electrons.

Given the two facts above, answer the question "Coal is used to produce the movement of electrons by what in coal-fire power stations?" with the following options: 
- cooling
 - energy
 - rotating
 - burning
 - heat
 - engines
 - mining
 - sun's heat


 

    burning     