All of the Following Are Primarily Associated with CD4 T-Cell

All of the following are primarily associated with CD4 T-cell function except

A) improve phagocytic mechanisms of tissue macrophages
B) assist B cells in the production of high-affinity antibodies
C) kill virus-infected cells
D) facilitate responses of other immune-system cells during infection
E) assist macrophages in sustaining adaptive immune responses through their secretion of cytokines and chemokines.