What do white blood cells do?

• A. They fight infection and consume dead tissue as well as producing antibodies that help the body resist infection
• B. They carry oxygen in the blood
• C. They form blood clots
• D. They transport nutrients and hormones

Answer: (A)

White blood cells defend the body against infection. They attack invading microbes, ingest and digest pathogens and debris, and some (like B cells) produce antibodies that help identify and neutralize threats. This combination of immune defense, cleanup, and antibody production best matches what white blood cells do. Other blood components handle oxygen transport (red blood cells), clotting (platelets), and the transport of nutrients and hormones (plasma).