Which of the following provides the best evidence that reinforcers do not simply strengthen behavior?

a. guinea pigs learned to turn their heads in a different direction when the behavior-reinforcercontingency was changed
b. cats made fewer errors after repeated escapes from a problem box
c. rats trained with bran mash made more errors in a maze when their reinforcer was switched to sunflower seeds
d. pigeons will peck at a key even when doing so results in a loss of food

Ans: c. rats trained with bran mash made more errors in a maze when their reinforcer was switched to sunflower seeds