Ncontrast to ectotherms, endotherms a. are more efficient in warm environments. b. need less to eat. c. create and conserve body heat better. d. maintain a lower metabolic rate.

The correct answer is C. create and conserve body heat better. Endotherms is just a scientific way of the common phrase that animals are warm-blooded, meaning they're not like lizards or snakes. Body heat is mostly produced as a result of metabolic activities, but there are animals with specific mechanisms for cases when there's no heat or in really cold areas.