<prompt> Plasma cells are derived from:T cellsB cellsMacrophagesNeutrophils  <response>: Ans. is b i.e., B cellsRef: Robbins 7the, p. 198, 199; Ananthanarayan, 9the, p. 136 An antigen interacts with the B lymphocyte that shows the best fit by virtue of its immunoglobulin surface receptor. When antigen binds to this BCR, the B cell is stimulated to divide and form a clone clonal selection. Such selected B cells proliferate and differentiate to become plasma cells that secrete antibody. 