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 10-mm calculus in the right lower ureter associated with proximal\nhydroureterone-phrosis is best treated with \nSelect and explain. \nA. ESWL, B. PCNL, C. Open ureterolithotomy, D. Ureteroscopic retrieval', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]