What is a fossil a ) an animal or plant that is extinct b)the bones of a dead organism c)the remains of an ancient organism d)an animal or plant that cannot evolve

A fossil is C. the remains of an ancient organism.
Fossils are the remains of prehistoric organisms preserved in earth or rock. Fossils can be the shape of a prehistoric plant or animal, or it can be traces of organisms, which includes things like tracks, footprints, or burrows.

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