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
The Fc piece of which immunoglobulin fixes C1 - 
Select and explain. 
A. IgA, B. IgG, C. IgM, D. IgE
C: IgM
Answer: C: IgM 
Explanation: IgM is paicularly effective at complement activation by binding to C1 Ref: Ananthanarayan & Parker's textbook of microbiology 9th edition pf:98