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': 'Reflex nephropathy is diagnosed mainly by: September 2005, September 2012 \nSelect and explain. \nA. X-ray KUB, B. Micturating cysto urethrogram, C. CT scan, D. MRI scan', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B: Micturating cysto urethrogram', 'role': 'assistant'}]