Imagine that you are a biologist who is attempting to get an accurate measure of an animal's basal metabolic rate. The best time to measure the metabolic rate is when the animal

A) is resting and has not eaten its first meal of the day.
B) is resting and has just completed its first meal of the day.
C) has recently eaten a sugar-free meal.
D) has not consumed any water for at least 48 hours.
E) has just completed 30 minutes of vigorous exercise.