June has been avoiding riding elevators since she was seven years old. when she is with other people, she makes excuses to use the stairs and feels relief upon avoiding elevator rides. june's fear of elevators is being maintained by reinforcement.

The answer is "negative reinforcement".

Negative reinforcement refers to a term portrayed by B. F. Skinner in his hypothesis of operant conditioning. In this a reaction or conduct is fortified by halting, evacuating, or maintaining a strategic distance from a negative result or aversive boost.