The term affinity refers to the strength of attraction between a single antigenic determinant and a corresponding antigen binding site. The term avidity refers to the total strength of the attraction between an antibody and a multivalent antigen. The reaction between an IgM molecule (which has 10 antigen binding sites), and a multivalent antigen is therefore much stronger than that of an IgG antibody (which has only 2 antigen binding sites).

Avidity is best described by which of the following statements: