Any stimulus or event that increases the probability of an operant when it is added.

Any stimulus or event that increases the probability of an operant when it is added.

• A. Emitted
• B. Discriminative Stimulus (SD)
• C. Negative Reinforcer
• D. Positive Reinforcer

Answer: (D)

Positive reinforcement is presenting a stimulus after a response that increases the likelihood of that response occurring again. The key feature here is that the added consequence strengthens the behavior. In this item, the defining idea is that the stimulus is added after the behavior and makes it more probable in the future, which is exactly what a positive reinforcer does. By contrast, a discriminative stimulus signals that reinforcement is available but isn’t a consequence that directly increases the behavior. A negative reinforcer increases behavior by removing an aversive stimulus, not by adding something. And “emitted” describes the behavior itself, not the nature of the consequence. An example: giving praise or a treat after a correct response strengthens that correct response in the future.

Positive reinforcement is presenting a stimulus after a response that increases the likelihood of that response occurring again. The key feature here is that the added consequence strengthens the behavior. In this item, the defining idea is that the stimulus is added after the behavior and makes it more probable in the future, which is exactly what a positive reinforcer does.

By contrast, a discriminative stimulus signals that reinforcement is available but isn’t a consequence that directly increases the behavior. A negative reinforcer increases behavior by removing an aversive stimulus, not by adding something. And “emitted” describes the behavior itself, not the nature of the consequence. An example: giving praise or a treat after a correct response strengthens that correct response in the future.