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': 'Transitional cell carcinoma bladder caused by \nSelect and explain. \nA. Schistosomiasis, B. Ascariasis, C. Malaria, D. None', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Risk factors for transitional cell carcinoma (TCC) of the bladder -\n1. Smoking → Major etiological factor.\n2. Occupational exposure to chemicals → Nephthylamine benzidine, aniline dyes, acrolein.\n3. Schistosoma haematobium (Bilharziasis) → It is a risk factor for both TCC & SCC.\n4. Drugs → Phenacetin \n5. Cyclophosphamide therapy \n6. Pelvic irradiation', 'role': 'assistant'}]