This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Etiological Factors of Neoplasia, Subject name: Pathology
[{'content': 'Uses of tumor marker are all except : \nSelect and explain. \nA. Screening of a cancer, B. Follow up of a cancer patient, esp. for knowing about recurrence, C. Confirmation of a diagnosed cancer, D. For monitoring the treatment of a cancer', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Tumor markers are not specific, so, cannot be used for confirmation of diagnosis. Confirmation is done by biopsy Examples: PSA Prostate cancer Ig Multiple myeloma hCG Choriocarcinoma Calcitonin Medulaary thyroid cancer Catecholamines Pheochromocytoma CEA Colon ca, Pancreatic ca CA 15.3 Breast cancer CA 19-9 Pancreatic cancer CA 125 Ovarian ca NSE Neuroblastoma', 'role': 'assistant'}]