TOEFL Reading: ETS-TOEFL阅读机经 - TJG1ZD9R1S811A9VL$

What can be inferred from the comparison of terrestrial animals to marine animals in the last sentence of paragraph 4? A. An animal's size is not the only factor affecting its metabolic rate. B. An animal's size determines what mechanism can be successfully used to prevent heat loss. C. Smaller animals are more successful than larger ones at preventing heat loss. D. Terrestrial animals have a wider variety of mechanisms for preventing heat loss than marine animals do.