This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immune system, Subject name: Medicine
[{'content': 'Anti histone antibodies are characteristics of \nSelect and explain. \nA. Drug induced lupus, B. Cardiac lupus, C. Lupus nephritis, D. MCTD', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ref - Harrison's internal medicine 20e p2517", 'role': 'assistant'}]