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': 'Which of the following immunoglobulin mediates primary immune response September 2011 \nSelect and explain. \nA. IgA, B. IgM, C. IgG, D. IgD', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B: IgM The antibody formed in the primary response is predominantly IgM and in the secondary response IgG', 'role': 'assistant'}]