The correct answers is D. Natural killer cell
Step-by-step explanation:
Natural killer cells are a type of cell in the immune system. These differ from other cells because these are innate, this means they attack all enemy cells or pathogens and are not specific. Also, they are the first general immune defense.
Moreover, the role of these cells to attack any enemy cell including cancer cells is possible due to specific chemicals or substances these cells release. One of these is perforins, which are mainly released by natural killer cells and destroy these by creating lesions in the cell membrane. According to this, the correct answer is D.