What is a key structural difference between IgM and IgG antibodies?

• A. IgG has a pentameric structure, while IgM is monomeric.
• B. IgM is a dimer, while IgG is a tetramer.
• C. IgM has a pentameric structure, while IgG is monomeric.
• D. IgM and IgG both have a dimeric structure.

Answer: (C)