This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
[{'content': 'Which of the following drug is used for medical treatment of gall stones \nSelect and explain. \nA. Clemastine fumarate, B. Mizolastine, C. Lovastatin, D. Ursodeoxycholic acid', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Dissolution therapy for asymptomatic cholestrol stones can be done with ursodeoxycholic acid,which is a bile acid that dissolves cholesterol.', 'role': 'assistant'}]