Why is the antigen-binding site crucial for antibody specificity?

Which of the following is NOT a class of antibodies?

A mutation occurs in the variable region of an antibody. What is the most likely outcome?

What is the role of somatic hypermutation in antibody diversity?

Which of the following best describes the role of V, D, and J gene segments in antibody diversity?

Why can't every possible antibody be encoded directly in the genome?

What is the primary role of the constant region in an antibody?