A Set of Mice Are Each Immunized with One of the Following

A set of mice are each immunized with one of the following as shown in Figure.
Mouse A is immunized with tetanus toxoid protein. Mouse B is immunized with the Haemophilus influenzae type b polysaccharide antigen. Mouse C is immunized with a conjugate of the diphtheria toxoid protein linked to H. influenzae type b polysaccharide. Mouse D is left unimmunized (naive) . Four weeks later the spleen cells from each mouse are isolated, and B lymphocytes and T lymphocytes from each spleen cell population are purified. When mixed together in culture together with a conjugate antigen of the tetanus toxoid protein linked to the to H. influenzae type b polysaccharide, which combination of spleen cells would generate a memory B cell response?

A) B lymphocytes from mouse B plus T lymphocytes from mouse B
B) B lymphocytes from mouse A plus T lymphocytes from mouse A
C) B lymphocytes from mouse C plus T lymphocytes from mouse A
D) B lymphocytes from mouse C plus T lymphocytes from mouse D
E) B lymphocytes from mouse B plus T lymphocytes from mouse D