Final answer:
T cells do not partake in phagocytosis, which is primarily carried out by phagocytes such as macrophages and dendritic cells. Cytotoxic T cells can induce apoptosis in infected cells, while CD4+ T cells (Helper T cells) secrete cytokines to aid B cells in producing antibodies. T cells also have CD3 antigens and can engage in antibody-dependent cellular cytotoxicity.
Step-by-step explanation:
The question revolves around the functions of different T cells in the immune system. T cells are not involved in phagocytosis; this role is primarily performed by phagocytes like macrophages and dendritic cells. T cells, such as Cytotoxic T cells (Tc), are specialized in killing target cells through mechanisms such as inducing apoptosis. They utilize perforins and granzymes for this purpose or may express Fas ligand to bind the Fas molecule on a target cell. Helper T (Th) cells, or CD4+ T cells, secrete cytokines that influence B cells and promote their differentiation into antibody-secreting plasma cells. Moreover, T cells have the CD3 antigen as part of their T cell receptor (TCR) complex, which is essential for TCR signal transduction. Concerning the options provided, T cells are indeed involved in antibody-dependent cellular cytotoxicity (ADCC), where they can kill target cells that have antibodies bound to their surface.