Natural killer (NK) cells ________.
A. are also called cytotoxic T cells
B. are a type of phagocyte
C. are cells of the adaptive immune system
D. can kill cancer cells before the immune system is activated
Answer:D
Natural killer (NK) cells ________.
A. are also called cytotoxic T cells B. are a type of phagocyte C. are cells of the adaptive immune system D. can kill cancer cells before the immune system is activated