The Cell-mediated response is a chain reaction of antigens and Interleukins that results in: A. The swelling of fluid and clotting elements to a damaged area.
B. The differentiation of helper T cells into cytotoxic T cells to destroy pathogens.
C. The production of macrophages to use phagocytosis on pathogens.
D. The differentiation of effector B cells into plasma cells to make antibodies.

The Cell-mediated response results in the production of macrophages to use phagocytosis on pathogens. The correct option is C.

Cell mediated immune response occurs when an invading antigen causes the release of cytokines (Interleukins), differentiation of T cells and production of macrophages.

Macrophages are produced through the differenciation of monocytes. They are further activated during an infection through the macrophage-activating cytokine (Interleukins).

Phagocytosis is the process used by immune cells such as macrophages  which involves ingesting and eliminating pathogenic microorganisms.

Cell-mediated response dosent result to differenciation of helper T cells into cytotoxic T cells rather it leads to the activation of cytotoxic T cells. Therefore B is wrong.

Cell-mediated response dosen't lead to the production of antibodies therefore option D is wrong.

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