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': 'Major immunoglobulin secreted by intestine ? \nSelect and explain. \nA. IgG, B. IgM, C. IgA, D. IgD', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., IgA", 'role': 'assistant'}]