In an experiment, monkeys learned to perform a discrimination task and select one of two containers. When the monkeys selected the "correct" container, they were rewarded with a slice of banana which they loved. After they had mastered the task, the experimenter switched to putting a piece of lettuce under the correct container. The monkeys were surprised and upset. This demonstrated that behavior is motivated by ___.

The expectation of a specific reinforcer

Explanation:

In the case of these monkeys, because they had developed an expectation of a specific reinforcer (banana), a switch to lettuce from banana could not go unnoticed, but instead, the switch came as a surprise to the monkeys and led to their frustration. During the training of the monkeys, the monkeys must have developed a strong expectation as it regards the reinforcer that would be presented, but the switch in the reinforcer altered the behavior of the monkeys which led to them refusing the lettuce. If it were in the case of a stimulus-response association, the switch might have not been noticed by the monkeys.

because the early people found out about it.

answer; francis cecil sumner;