In Order for B Cells to Produce Antibodies and Cytotoxic

In order for B cells to produce antibodies and cytotoxic T cells to attack infected host cells, they must first

A) recognize self markers, develop specificity for the markers, and then produce clones.
B) be activated by interleukins, encounter an antigen, and then develop specificity toward it.
C) encounter an antigen, develop specificity for that antigen, and then remember the antigen.
D) undergo maturation, encounter their specific antigen target, and then become activated through cytokines.