What is the primary function of antibodies?

• A. They neutralize pathogens
• B. They digest fats
• C. They transport oxygen
• D. They regulate body temperature

Answer: (A)

Antibodies are specialized proteins produced by B cells that recognize and bind specifically to antigens on pathogens or toxins. This binding can neutralize the threat directly by blocking a pathogen’s ability to infect cells or by inactivating toxins, and it also flags the invader for attack by other parts of the immune system, such as phagocytes or the complement system. In short, their main function is to protect the body by targeting and neutralizing specific threats. The other ideas describe different bodily roles—digesting fats is the job of digestive enzymes, transporting oxygen is handled by hemoglobin in red blood cells, and regulating body temperature is controlled by the brain and metabolic processes.