Deepti:
Are you getting these questions from the PrepCast exam simulator? If so, I believe that explanations are given for each question. If you're not, then you need to speak to the company that wrote the question.
But, to answer your immediate question:
The correct answer is D. No "reprimands" are required or desired. A corrective action corrects a defect in process or product, and are performed without change requests. Even more so if the corrective action will not impact project baselines. So, A and B are eliminated. "Do nothing" is NEVER an apropiarte answer for the PMP exam., so C is eliminated as well.
Harry