Index fossils are found throughout the world and come from organisms which existed during limited periods of geologic time. Which of the following best describes what index fossils can be used to determine? A.
the age of a layer of rock
B.
the way an organism went extinct
C.
when an organism first appeared on Earth
D.
how an organism evolved over time

The index fossils can be used to determine the age of a layer of rock and how an organism evolved over time

Fossils gives geologist some information about the organism that lived in the past because when those organism dies, they decay and goes deep into the lithosphere.

Index fossils refers to those fossils used by geologists to determine the relative age of rock strata or other fossils with ease.

The index fossils can be used to determine:

Hence, the Option A and C is correct.

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radioactive dating, also known as  radioisotope dating  is a process that in  estimating the approximate  age  of  rocks. these data can be analyzed from  the studies dealing with the  decay of the radioactive elements that are present in these rocks. in nature, there are a few types of materials or atoms which are quite unstable and they spontaneously decay or breakdown to form other kinds of atoms.

(d). gave voting rights to free african americans and white women.