Which of the following correctly matches a leukocyte type with its primary function?

• A. Neutrophils — phagocytosis; lymphocytes — adaptive immunity; monocytes — macrophage formation.
• B. Neutrophils — antibody production; lymphocytes — phagocytosis; monocytes — blood clotting.
• C. Neutrophils — oxygen transport; lymphocytes — plasma cell formation; monocytes — hematopoiesis.
• D. Neutrophils — mucus secretion; lymphocytes — allergen response; monocytes — cartilage formation.

Answer: (A)

Leukocytes have specialized defense roles. Neutrophils are the rapid responders that perform phagocytosis, engulfing and destroying bacteria. Lymphocytes are central to adaptive immunity, with T cells coordinating cell-mediated responses and B cells producing antibodies. Monocytes circulate in the blood and, when they enter tissues, differentiate into macrophages that continue phagocytosis and help coordinate immune activity.

This aligns with the correct match: neutrophils with phagocytosis, lymphocytes with adaptive immunity, and monocytes with macrophage formation.

Other pairings mix up these roles. Antibody production is a function of lymphocytes (B cells), not neutrophils. Phagocytosis is not a primary role of lymphocytes. Blood clotting involves platelets and coagulation factors, not monocytes.