This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
[{'content': 'Tumor marker for Breast cancer? \nSelect and explain. \nA. CA 15-3, B. CA 19-9, C. CA 125, D. CEA', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Tumor MarkersTumor TypesCA-125 Ovarian cancerCA 19-9 Colon and Pancreatic cancerCA 15-3 Breast cancerCEACarcinomas of the colon, pancreas, lung, stomach, and heaRef: Robbins and Cotran Pathologic Basis of Disease; 9th edition; Chapter 7; Neoplasia; Page no:337; Table: 7-12', 'role': 'assistant'}]