Which white blood cells contain enzymes to digest and kill bacteria and parasites, and also respond to allergies?

• A. Erythrocytes
• B. Lymphocytes
• C. Platelets
• D. Leukocytes

Answer: (D)

White blood cells, or leukocytes, are the immune cells responsible for attacking pathogens and coordinating allergic responses. They carry enzymes and antimicrobial substances that allow them to digest and kill bacteria and parasites. Within this group, eosinophils and basophils play notable roles in allergies, with eosinophils helping fight parasites and modulating allergic reactions, and basophils releasing histamine during allergic responses. Among the given choices, leukocytes encompass the cells that perform these digestion and allergy-related functions, whereas erythrocytes are red blood cells, platelets are involved in clotting, and lymphocytes are just one type of white blood cell focusing on specific immune responses.