This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and breast, Subject name: Anatomy
[{'content': 'Best investigation to differentiate scar from recurrence after mastectomy done for carcinoma breast \nSelect and explain. \nA. MRI, B. CT, C. PET Scan, D. Mammography', 'role': 'user'}, {'content': 'Answer: C \nExplanation: PET Scan Investigation of choice for recurrences in scarred breast. UUseful in multifocal disease and in helping detect axillary involvement Ref:Sabiston 20th edition pgno : 826-828', 'role': 'assistant'}]