In Tolman’s maze study, the fact that the group of rats receiving reinforcement only after day 10 of the study solved the maze far more quickly than did the rats who had been reinforced from the first day can be interpreted to mean that these particular rats

a. were very hungry and therefore learned much more quickly.

b. were much smarter than the other rats.

c. had the opportunity to cheat by watching the other rats.

d. had already learned the maze in the first 9 days.