Answer:
Lymphocytes
Step-by-step explanation:
White blood cells ( leukocytes) is one of the formed elements of blood that provides immunity and protection against the pathogens. Different types of leukocytes are eosinophils, basophils, monocytes, lymphocytes and neutrophils.
Lymphocytes are B cells and T cells of the immune system. B cells produce antibodies against the antigen and T cells kills the harmful cells of the body. by specific cell determinants.These cells are not capable of phagocyte the pathogen.
Thus, the correct answer is option (A).