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: Microbiology
[{'content': 'In patients with asthma due to an allergic cause, the\nserum levels of which immunoglobulin increases? \nSelect and explain. \nA. IgD, B. IgM, C. IgA, D. IgE', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]