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': 'A 65 year old male smoker presents with gross total painless hematuria. Which of the following is the most likely diagnosis? \nSelect and explain. \nA. Cystolithiasis, B. Carcinoma prostate, C. Carcinoma of urinary bladder, D. Benign prostatic hyperplasia', 'role': 'user'}, {'content': "Answer: C \nExplanation: Patient in the question is 65 years old and is a smoker, both these factors predispose to the development of bladder carcinoma. And he is presenting with painless hematuria which is by far the most common symptom and indicator of bladder carcinoma until proven otherwise. Ref: Bailey and Love's Sho Practice of Surgery, 23rd Edition, Pages 1360-3.", 'role': 'assistant'}]