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': 'Which immunoglobulin is scarce in human serum- \nSelect and explain. \nA. IgA, B. IgG, C. IgM, D. IgE', 'role': 'user'}, {'content': "Answer: D \nExplanation: IgE is an 8 S molecule. - resemble IgG structurally. - heat liable - affinity for the surface of tissue cells of the same species. - normal serum contains only traces of IgE ( a few nanograms per ml ) - greatly elevated levels in atopic conditions like asthma, hay fever. REF:Anathanarayan & paniker's 9th edition, pg no: 98,98 <\\p>", 'role': 'assistant'}]