Which antibody class is initially produced by plasma cells and how do they switch to another class?

• A. IgA is initially produced, and class switching requires antigen exposure.
• B. IgE is initially produced, and class switching is achieved through alternative splicing.
• C. IgM is initially produced, and class switching involves DNA recombination events that change the constant region.
• D. IgG is initially produced, and class switching involves mutations in the variable region.

Answer: (C)