This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'Screening of prostate CA is best done by \nSelect and explain. \nA. PET CT, B. PSA, C. DRE, D. DRE + PSA', 'role': 'user'}, {'content': 'Answer: D \nExplanation: DRE + PSA is the best way to screen prostate Ca.', 'role': 'assistant'}]