A Paleontologist Discovers the Fossilized Heart of an Extinct Animal

Multiple Choice

A paleontologist discovers the fossilized heart of an extinct animal. The evidence indicates that the organism's heart was large, was well-formed, and had four chambers, with no connection between the right and left sides. Which of the following conclusions is best supported by these observations?

A) the animal had evolved from birds
B) the animal was endothermic and had a high metabolic rate
C) the animal was most closely related to alligators and crocodiles
D) the animal had little to no need to regulate blood pressure