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': 'Carcinoma of lung, breast marker is - \nSelect and explain. \nA. CEA, B. AFP, C. 11CG, D. CA-15-3', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., CEA o Carcinoembryonic antigen is a marker in cancer of colon, pancreas, lung, breast, and ovary.", 'role': 'assistant'}]