Answer: Strengthening a behavior by contingently withdrawing something displeasing.
Explanation: Negative reinforcement refers to the strengthening and motivating the behavior by the elimination of the negative outcome or stimulus by means of stopping, removal, avoidance etc .
So, anything that is unpleasant or displeasing is withdrawn from the behavior.Other options are incorrect because behavior is not weakened by this act and no pleasing factors are removed from the behavior.