Which of the following would make the best index fossil? 1 point
A. An insect that only existed in one small forest for about 100 million years.
B. An aquatic animal that existed all over the world for about 15 million years.
C. A single-celled organism that lived in a widespread region for about 25 million
years.
D. A plant species that lived in a specific geographic region for about 5 million years.