This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Anatomy
[{'content': 'What is the percentage of immunoglobulins present in proteins? \nSelect and explain. \nA. 5%, B. 10%, C. 15%, D. 20%', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Immunoglobulins constitute 20 to 25% of total serum proteins. Based on physiochemical and antigenic differences, five classes of immunoglobulins have been recognized: IgG, IgA, IgM, IgD, and IgE.(Ref: Ananthanarayan 9th edition, p93)', 'role': 'assistant'}]