Which of These Statements Concerning B Cell Receptors (BCRs) Is

Which of these statements concerning B cell receptors (BCRs) is incorrect?

A) Scientists estimate that each person forms at at least 109 different types of B lymphocytes with a set of distinct BCRs.
B) Each B lymphocyte is randomly generated with antibody- variable regions that determine its BCR.
C) They are complementary in shape to the antigenic determinants of antigens that they may or may not encounter.
D) They are formed in response to an encounter with an antigen.
E) They are bound to the surface of B lymphocytes and have two antigen- binding sites.