Difference between paleolithic age and mesolithic age

The difference between Paleolithic and Mesolithic periods can be related to the differences in human life and how they evolved during these two periods. Paleolithic and Mesolithic are two of the pre-historic eras of human existence. To be more specific, these are two stages of the stone age. These two eras are considered as significant because they bear evidence to the earliest existence of humans and culture. 

c or d both can be the answer