Administering an aversive stimulus following an operant response is

Administering an aversive stimulus following an operant response is positive punishment.

Explanation:

In operant conditioning, punishment is a strategy used to decrease the appearance of a behavior, contrary to a reinforcement, that aims to increase the apperance of a behavior.

Punishment can be either positive or negative, and although positive punishment may sound like a contradiction, in conditioning, positive doesn't refer to something good just like negative doesn't refer to something bad. Positive punishment means that a undesired or aversive stimulus is added to a behavior, a punishment is added in order to avoid the behavior or response.

Meanwhile, a negative punishment means that a desired stimulus is taken away as a punishment and as a way to avoid a behavior or response.