This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
An operant condition where paradigm pain stimulus is given to a child for decreasing a certain undesired behaviour can be classified as - 
Select and explain. 
A. Positive reinforcement, B. Negative reinforcement, C. Punishment, D. Negotiation
C: Punishment
Answer: C: Punishment 
Explanation: Reinforcement
Positive reinforcement:- A reward is given on the performance of the desired behavior.
Negative reinforcement:- On the performance of the desirable behavior, punishment is avoided.
Punishment:- On performing an undesired behavior, an aversive stimulus (paradigm pain in this question) is given.
Note-The basic difference between reinforcement and punishment is that reinforcement (Positive or negative) is to promote desired behavior, on the other hand, punishment is to decrease undesired behavior.