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': 'The predominant constituent of the pale yellow gall stones in the gall bladder is - \nSelect and explain. \nA. Mucin glycoprotein, B. Calcium carbonate, C. Cholesterol, D. Calcium phosphate', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]