The Graph Below Shows the Extinction Rates for Families of Marine

Multiple Choice

The graph below shows the extinction rates for families of marine organisms over different periods of Earth's history.What is the best estimate for the background extinction rate given these data?

A) 14-20 families per million years
B) 8-12 families per million years
C) 2-5 families per million years
D) 2-20 families per million years