This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Which of the following pigment s are involved in free radical injury \nSelect and explain. \nA. Lipofuscin, B. Bilirubin, C. Melanin, D. Hematin', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref, Robbins 7/ep39,9/e p64', 'role': 'assistant'}]