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
Best investigation to differentiate scar from recurrence after mastectomy done for carcinoma breast 
Select and explain. 
A. MRI, B. CT, C. PET Scan, D. Mammography
C: PET Scan
Answer: C: PET Scan 
Explanation: 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