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': 'The earliest immunoglobulin to be synthesized by the fetus is- \nSelect and explain. \nA. IgA, B. IgG, C. IgE, D. IgM', 'role': 'user'}, {'content': "Answer: D \nExplanation: IgM constitutes 5-8 percent of serum immunoglobulin with a normal level of 0.5-2 mg per ml. it is the earliest immunoglobulin to be synthesized by the fetus, beginning by about 20 weeks of age. - it is not transpoed across the placenta, presence of IgM in newborn or fetus indicates intrauterine infection. REF:Anathanarayan & paniker's 9th edition, pg no: 98 <\\p>", 'role': 'assistant'}]