Which of the following was a reason that behaviorism lost its appeal?
a. its methods were not precise enough.
b. it focused too much on internal representations.
c. it could not explain higher-level cognitive processes.
d. its ideas could not be specified mathematically.

The answer is C. It could not explain higher-level cognitive processes.

Explanation:

One of the main reasons why the behaviorist perspective lost its appeal and other perspectives, such as humanism, gained more strenght, is that, by explaining human behavior only in terms of responses to a stimulus, it failed to explain higher-level cognitive processes. It didn't provide the theoretical tools to analyze behavior that was not motivated by a stimulus or a reward or behavior that took place even after knowing that their would be a punishment.