<prompt> Components of Innate immunity that are active against viral cells includes -NK cellsCytotoxic cellsB-cellMemory B cell  <response>: A class of lymphocytes called natural killer cells or NK cells are impoant in nonspecific defense against viral infections and tumors. They selectively kill virus-infected cells and tumors cells. - they are activated by interferons. Reference : Anathanarayan panikers 9th edition, pg no:81 p 