Which of these mechanisms do cytotoxic t (tc) cells use to destroy a target--that is, deliver a lethal hit?

Cytotoxic T cells use two basic mechanisms to destroy target cells: 1. Cytotoxic T cells release perforins which create pores on the target cells and granzymes which stimulate the apostosis of the target cells by exocytosis. 2. Cytotoxic T cells bind specific membrane receptors on the target cells and stimulate apostosis process which eliminate the target cells.

The answer to this question is PERFORATION OF THE MEMBRANE. Actually, the Cytotoxic T cells are the ones that kill cancer cells, and other cells that are infected or damaged. What this cytotoxic T cells do is that they release cytotoxins and this would result to apoptosis or cell death. How this is effectively done is through the perforation of the membrane.