IgM Antibodies Are Much More Efficient Than IgG at Activating

IgM antibodies are much more efficient than IgG at activating the complement cascade. However, under certain circumstances, IgG antibodies will activate the complement pathway. One example of a situation in which IgG binding to its antigen will not trigger the complement cascade is when:

A) The IgG antibodies bind to a multivalent soluble antigen in solution, such as a polysaccharide structure shed from a bacterial pathogen.
B) The IgG antibodies bind to a viral capsid protein that is present in more than 100 copies on the viral particle surface.
C) The IgG antibodies bind to a bacterial surface by recognizing a repetitive polysaccharide component of the bacterial capsule.
D) The IgG antibodies are binding self-antigens such as chromatin released from dead cells.
E) The IgG antibodies are neutralizing a bacterial toxin protein by blocking the receptor-attachment site on the toxin.