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 ds DNA antibody is specific for \nSelect and explain. \nA. SLE, B. Systemic sclerosis, C. CREST syndrome, D. Sjogren's syndrome", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ref image- Harrison's internal medicine 20e p2517", 'role': 'assistant'}]