If being buried under soil and mud changes peat into coal through extreme heat and pressure in a wetland over a long period of time, then where does being buried under soil and mud change peat into coal through extreme heat and pressure over a long period of time?

Answer choices:
- watershed
 - alluvial
 - wetland
 - deltas
 - erosion
 - houses
 - earth
 - lakes

 

   wetland       