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: Surgery
[{'content': 'Sq. cell tumor of urinary bladder is due to -a) Stoneb) Schistosomiasisc) Chr. cystitisd) Diabetes mellitus \nSelect and explain. \nA. ab, B. bc, C. abc, D. bcd', 'role': 'user'}, {'content': "Answer: C \nExplanation: Risk factors for squamous cell ca of bladder\n\nSchistosoma haematobium\nit's a risk factor for both TCC & sq. cell ca, but more for sq. cell ca.\nChronic irritation from urinary calculi, long term indwelling catheters, chronic urinary infections\nBladder diverticula", 'role': 'assistant'}]