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: Medicine
[{'content': 'Stone which is resistant to lithotripsy: \nSelect and explain. \nA. Calcium oxalate, B. Triple phosphate stone, C. Cystine stone, D. Uric acid stone', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Answer is C (Cystine stones): Cystine stones are most resiatnt to Lithorriosy.', 'role': 'assistant'}]