You are presented with the question "What does vegetation change into after being buried under soil?" and the following answer choices: 
- desert
 - space
 - grass
 - blankets
 - bushes
 - time
 - roots
 - fuel

Now knowing that being burried under soil and mud changes vegetation into peat through extreme heat and pressure in a swamp over a long period of time and peat moss from bogs is also useful in gardens and as an alternative fuel source, choose the best answer.


 

        fuel 