Which Statement About the Humoral Immune Response Is Correct

Which statement about the humoral immune response is correct?

A) The activation phase occurs in the thyroid.
B) Cytokines stimulate proliferation of T-helper cells in the activation phase and B cells in the effector phase.
C) Plasma cells produced during the activation phase stimulate naïve B cells with the same specificity to produce antibodies in the effector phase.
D) B-cells are antigen-presenting cells in the activation phase, and macrophages are antigen-presenting cells in the effector phase.
E) B cells display antigenic fragments on Class I MHC proteins.