How do index fossils scientists? a. they aid in the study of ranges of different organisms. b. they advance understanding of the origin of life on earth. c. they aid in comparison of rock layers at distant locations. d. they advance understanding of rock type at the time the organism lived.

C. They aid in comparison of rock layers at distant locations

Explanation: Using the law of superposition, scientists can tell the relative age of the rock layer by the age of the species of the fossils that reside in the rock laters.

C

Explanation:

They aid in comparison of rock layers at distant locations.

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