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" deformity in excretory urogram occurs in? \nSelect and explain. \nA. Hydronephrosis, B. Polycystic kidney, C. Uretrocele, D. Renal agenesis', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Polycystic kidney", 'role': 'assistant'}]