This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'First antibody produced by newborn? \nSelect and explain. \nA. IgA, B. IgG, C. IgE, D. IgM', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ref: Microbiology by Ananthanarayan 9th ed. 198-99* First antibody produced by newborn is IgM at 20 weeks age of gestation.* Immunoglobulin that can cross placenta: IgG1 * Immunoglobulin that is present in breast milk: IgA', 'role': 'assistant'}]