How do antibodies bind their target antigens?

Antibodies are made up of light chain and heavy chains. Heavy chain contains one variable region and three constant region while light chain have only one variable region and one constant region.

The variable region of the light chain and heavy chain of the antibody together makes the antigen-binding site called paratope which binds to their target antigen by non-covalent bond.

Epitope is the portion of an antigen that is recognized by the antibody and then the antibody binds to the epitope of antigen through its paratope region and helps in the killing of antigen.

c should be the answer