Which Statement Is Correct

Multiple Choice

Which statement is correct?

A) The thermoneutral zone of an endotherm is bounded by a lower critical temperature and an upper critical temperature.
B) Below the thermoneutral zone, an endotherm's thermoregulatory responses do not require a lot of energy.
C) Above the thermoneutral zone, an endotherm's thermoregulatory responses do not require a lot of energy.
D) Within the thermoneutral zone, an endotherm's thermoregulatory responses require a lot of energy.
E) At temperatures well outside the thermoneutral zone, endotherms can still maintain their body temperatures without expending additional energy.