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': 'Lithogenic bile contains an increased amout of - \nSelect and explain. \nA. Bile acid, B. Bile salt, C. Cholesterol, D. Bilirubin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]