Geologists have divided earth's history into time units, which are largely based on
a. oral histories.
b. written correspondences.
c. fossils.
d. climates.

Geologists have divided Earth's history into time units, which are largely based on fossils. The correct option among all the options given in the question is option "c". A Geological Time Scale or GST has been effectively used by geologists, paleontologists and variety of other people related to earth science. It is been already determined that the Earth is approximately 4.54 billion years old.

3.1439 im dont think its right but im pretty sure it is

Increasing the release of greenhouse gases and pollution