Decomposition is the process by which break(s) down over time. A.
soil, sand, and rocks
B.
dead plants and animals
C.
mountains
D.
natural gas

its B

Explanation:

dead plants and animals is the correct answer, ik A, C, D all sound correct but its not so i hope this help for anybody far behind like me lol

answer(c) carved on a babylonian clay tablet that showed earth as a flat circular disk;