Answer:
Place tantrum on extinction
Explanation:
Extinction is an explanation of the behavior. Extinction is a behavior that gradually weakening the conditioned response of a person or animal. The result of extinction will be the extinction of the behavior or disappear conditioned response or behavior. Conditioned behavior will stop eventually.
Thus in the above statement William, a 20th-month-old child was making life very miserable for his parents because of having temper tantrums. But when parents stayed with him. He does not do the behavior. Parents need to place his tantrum on extinction through conditioning.