The law of effect refers to the .
a. tendency to repeat behaviors that are rewarded.
b. enhance conditioning using strict responses.
c. learn in the absence of reinforcement.
d. lose intrinsic interest in an over-rewarded activity.
e. learn associations between consecutive stimuli.

a. tendency to repeat behaviors that are rewarded.

Explanation:

The law of effect is a psychological principle that was propounded by Edward Thorndike in 1898 states that responses that bring satisfying effects are more likely to be repeated when such situation occurs again and also, responses that bring dissatisfying responses are less likely to be repeated when the situation occurs again.

So the law of effect refers to the tendency to to repeat behaviors that are rewarded and not to repeat behaviors that are not rewarded.