Fact 1: Heat and pressure change the remains of prehistoric living things into natural gas.

Fact 2: Natural gas is a fossil fuel.

Given the two facts above, answer the question "Heat and pressure upon fossils creates what?" with the following options: 
- snow
 - energy
 - food
 - ecosystems
 - erosion
 - fossil fuels
 - forces
 - Energy.


 

      fossil fuels   