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': 'Rupture of membranous Urethra occurs more commonly due to \nSelect and explain. \nA. Thin unsupported wall, B. Fixity of Urethra, C. Angulation, D. Proximity to bladder', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]