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
True about immunoglobulins - 
Select and explain. 
A. IgE has minimum concentration, B. IgG has minimum concentration, C. IgA has minimum concentration, D. IgM has minimum concentration
A: IgE has minimum concentration
Answer: A: IgE has minimum concentration 
Explanation: Of IgE is typically the least abundant isotype--blood serum IgE levels in a normal individual are only 0.05% of the Ig concentration Ref: Ananthanarayan & Panikers textbook of microbiology 9th edition pf:98