If a POSITIVE REINFORCER is added after a behavior and the behavior is strengthened/increased, the process used is called:

A) negative reinforcement.
B) positive reinforcement.
C) extinction.
D) punishment.

Positive reinforcement involves adding a desirable stimulus (positive reinforcer) after a behavior to increase the likelihood of that behavior occurring again in the future. This is opposite of punishment, where an undesirable consequence is applied after a behavior to decrease the likelihood of it occurring again in the future. Extinction involves withholding reinforcement for a behavior, which can eventually decrease the frequency of that behavior. Negative reinforcement involves the removal of an aversive stimulus after a behavior, which also increases the likelihood of that behavior occurring again in the future.