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: Biochemistry
[{'content': 'Bile acids are formed from \nSelect and explain. \nA. Cholesterol, B. Amino acids, C. Bilirubin, D. Lipoproteins', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]