Do you happen to have the full version of the question? I would love to help you out but the question is missing a lot of details in order for us to come up with a correct answer.
If this is indeed the full question from another exam simulator, I can tell you with my experience that it doesn't reflect correctly to the actual PMP exam question. If you are looking for a quality exam simulator you can try the free Precast exam simulator to compare the difference.
I am stuck at below question, what is the correct answer and why?
If a subcontractor from the already running project has service quality control issue, what should PM refer to?
A. Procurement Mgt Plan
B. Quality Mgt Plan
Training for Project Management Professional (PMP)®, PMI Agile Certified Practitioner (PMI-ACP)®, and Certified Associate in Project Management (CAPM)®