Whenever Rod sees his Uncle Ben, he smiles and says "Candy, please." Uncle Ben always gives him a Lifesaver. However, Uncle Jim, the dentist, will not give Rod candy when he asks for it. So eventually Rod only asks for candy from Ben, and not from Jim. This is an example of ____.

Stimulus discrimination is defined as the mechanism in which response is given to actual stimulus only and rest of stimulus similar in nature are avoided or differentiated . It is the previous stimulus that persist stimulus control on the action and behavior that is reinforced.

According to the question, Rod asks for candy only from Uncle Ben because he gives him candy every-time as response but Uncle Jim does not provide him candy when Rod approaches him.Thus, Rod asks for candy from actual stimulus only(Uncle Ben) and differentiate with other stimulus (Uncle Jim).