For which of the following phenomena is intrinsic affinity necessarily more important than functional affinity?
A. Antibody-mediated opsonization of encapsulated bacterial pathogens
B. Assay using antibodies to detect small drugs in solution
C. Binding of C1q to immunoglobulin G (IgG) or IgM
D. Binding of neutralizing IgG antibodies to nonenveloped viruses​