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': 'Spider-leg appearance is seen in: March 2010 \nSelect and explain. \nA. Pyelonephritis, B. Polycystic kidney, C. Renal aery stenosis, D. Ureteric stones', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B: Polycystic kidney', 'role': 'assistant'}]