Which term refers to a stimulus that signals a behavior will be reinforced?

The term that refers to a stimulus that signals a behavior will be reinforced is called a discriminative stimulus. In the context of operant conditioning, the discriminative stimulus acts as a cue or signal, indicating that a specific behavior will lead to a reinforcement if performed. For instance, if a dog learns that sitting in response to a cue word like "sit" will result in receiving a treat, the cue word itself becomes a discriminative stimulus. This mechanism helps animals, including dogs, learn which behaviors are likely to be rewarded in different contexts.

The other terms listed do not serve this function. An unconditioned stimulus refers to a stimulus that naturally and automatically triggers a response without prior learning, while a positive reinforcer is an outcome that increases the likelihood of a behavior occurring again but does not signal that reinforcement will happen. A conditioned response is a learned reaction to a previously neutral stimulus after it has been paired with an unconditioned stimulus. None of these terms correctly denote the function of signaling reinforcement in the way that discriminative stimulus does.