Fact 1: Coal is used for generating heat by burning.

Fact 2: Coal forms from dead plants, compacted.

Given the two facts above, answer the question "What can generate heat?" with the following options: 
- time
 - siren
 - electricity
 - Ice cube
 - Dead plants
 - Fuel cells
 - kinetic energy
 - Nematoda


 

     Dead plants    