Fossils are formed when plants or animals are

A. Buried under a tarp.

B. Preserved in oceans, lakes and rivers.

C. buried under mud.

D. Swallowed by other living creatures.

This is a trick question the answer can be either B or C. Mud from the hardening and encasing of materials whereas it can also be B because water can freeze into also glacier preserving the animal.

C.) Buried under mud. Fossils form when the mud traps the plant/animal and hardens, cementing the form of the body, which is a fossil.