The Greatest Advantage of Using Animals Over Human Subjects in Psychopharmacological

The greatest advantage of using animals over human subjects in psychopharmacological research is that

A) assessing emotional and psychological changes in response to experimental manipulations is relatively straightforward in nonhuman subjects.
B) living conditions, such as stress level, diet, exercise, etc. can be precisely controlled.
C) animals are much less likely to express stress in test conditions.
D) animals recover much more quickly from drug experiments.