The Extinction of the Dinosaurs Has Been Associated with

The extinction of the dinosaurs has been associated with

A) a virus leading to disease and massive loss of life.
B) dinosaurs preying upon each other until they became extinct.
C) a meteor impact at the end of the Cretaceous Era that caused major cooling.
D) new chemicals and ions in the environment which caused dinosaurs to become sterile.
E) mammals who were more adapted and more able to acquire similar resources.