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

Fact 2: Evidence of prehistoric life includes many dinosaur footprints found in coal mines.

Given the two facts above, answer the question "what gets changed into natural gas due to heat and pressure?" with the following options: 
- mussels
 - oxygen
 - glass
 - clams
 - animals
 - Most plants
 - temperature
 - dinosaurs


 

        dinosaurs 