Cytotoxic Effector T Cells Also Produce Inflammatory Cytokines Such as IFN-

Cytotoxic effector T cells also produce inflammatory cytokines such as IFN- $\gamma$ and TNF- $\alpha$ when their T-cell receptor recognizes peptide:MHC on a target cell. One effect of this cytokine secretion is to enhance the ability of CD8 effector T cells to recognize and kill other infected cells in the nearby vicinity. This enhanced activity is due to:

A) The increased production of perforin and granzymes by CD8 cells
B) The up-regulation of MHC class I protein expression by IFN- $\gamma$
C) The ability of TNF- $\alpha$ to induce vascular leakage
D) The effect of cytokines on promoting target cell apoptosis
E) The effect of IFN- $\gamma$ to enhance viral replication leading to increased viral antigen presentation