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: Pathology
[{'content': 'ck 7 negative and ck 20 negative tumor is \nSelect and explain. \nA. Prostate carcinoma, B. Carcinoma colon, C. Urothelial carcinoma, D. Mesothelioma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Answer- A. Prostate carcinomaCK7- 1 CK20 - carcinoma of adrenal coex, prostate', 'role': 'assistant'}]