Elton's mother has been nagging and nagging that he should stop fooling around with his guitar and start studying. Finally, in order to stop her nagging, Elton complies and hits the books. This example illustrates the effect of .
A. positive reinforcement
B. negative reinforcement
C. positive punishment
D. negative punishment

B. Negative Reinforcement.

Explanation:

This is simply explained as discomfort in a person when that which he/she needs to be done immediately is been neglected. In negative reinforcement, a response or behavior is strengthened by stopping, removing, or avoiding a negative outcome or aversive stimulus.

Aversive stimuli tend to involve some type of discomfort, either physical or psychological. Behaviors are negatively reinforced when they allow you to escape from aversive stimuli that are already present or allow you to completely avoid the aversive stimuli before they happen.