Answer:
The answer is D. Cleaning your room to avoid your roommate's nagging, is an example of a negative reinforcer.
Explanation:
In operant conditioning there are two strategies to modify behavior, through reinforcement and through punishment. Reinforcement is targeted to repeat a wanted action or behavior and punishment is used when a certain behavior wants to be eliminated; there are two types of reinforcers, positive and negative, a positive reinforcer is a pleasant stimulus that is given when the desired behavior takes place, a negative reinforcer, however, is taking away or avoiding an unpleasant stimulus as a reward when the desired behavior takes place.
In this case, you clean your room to avoid an unpleasant stimulus, that is your roommate's nagging, therefore, it is a negative reinforcer, that can take you to repeat the desired behavior, that is, cleaning your room.
