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': 'What is true about carcinoma bladder ? \nSelect and explain. \nA. Common in smokers, B. Commoner in females than that in males, C. Mostly adenocarcinoma, D. Pain in suprapubic region is the first symptom', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Common in smokers Bladder cancer is 2.5 times more common in men than women.", 'role': 'assistant'}]