What does the principle of faunal succession state?
A) Rock layers with the same unique grouping of fossils are of the same geologic age.
B) Fossils are deposited in approximately horizontal layers and spread out until they reach a barrier.
C) Specific groups of organisms have followed one another in a definite sequence trough the earth's history.
D) Absolute dating is required to determine the relative age of animals based on their fossils.