How Do Mass Extinctions Differ from Background Extinctions

Multiple Choice

How do mass extinctions differ from background extinctions?

A) Mass extinctions occur over a longer period of time than background extinctions.
B) Mass extinctions, but not background extinctions, are generally caused by competition.
C) Mass extinctions cause a larger proportion of organisms to go extinct than background extinctions.
D) Mass extinctions typically result from Hox gene mutations, and background extinctions typically result from changes in weather patterns.