This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
Hemagglutinin (AntiA and Anti B) are which type of antibodies - 
Select and explain. 
A. IgG, B. Ig M, C. IgA, D. IgE
B: Ig M
Answer: B: Ig M 
Explanation: Ans. is 'b' i.e., IgM