Which of the Following Statements Regarding Immunoglobulins Is Correct

Multiple Choice

Which of the following statements regarding immunoglobulins is correct?

A) Immunoglobulins make up five classes (or isotypes) called IgA,IgD,IgE,IgG,and IgM.
B) Regardless of their isotype,immunoglobulins all have the same effector function.
C) Antibodies consist of four identical heavy chains and four identical light chains.
D) Peptide bonds hold the heavy and light chains together.
E) The constant regions make up the antigen-binding site.