Any stimulus that,when removed after a response,strengthens the response is called a(n)

A) conditioned stimulus.
B) unconditioned stimulus.
C) positive reinforcer.
D) negative reinforcer.

A negative reinforcer is any stimulus that removes an aversive or unpleasant consequence, therefore increasing the likelihood of the behavior being repeated in the future. This is different from a positive reinforcer, which adds a desirable consequence to increase the likelihood of a behavior being repeated. A conditioned stimulus is a neutral stimulus that becomes associated with an unconditioned stimulus through classical conditioning, and an unconditioned stimulus is a stimulus that naturally triggers a response without any conditioning.