Which of the following statements about the actions of antibodies in the immune response is correct?

• A. Antibodies function exclusively inside the nucleus of infected cells.
• B. Antibodies neutralize pathogens by binding to their surface antigens, preventing them from infecting host cells.
• C. Antibodies are only produced during innate immune responses.
• D. Antibodies directly destroy pathogens by phagocytosis.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the role of antibodies in the immune system. Antibodies are proteins produced by B cells that specifically recognize and bind to antigens on pathogens.
2. Step 2: Recall that antibodies primarily function outside of cells, in bodily fluids, by binding to antigens on the surface of pathogens to neutralize them or mark them for destruction.
3. Step 3: Evaluate the statement about antibodies functioning exclusively inside the nucleus of infected cells. This is incorrect because antibodies do not enter the nucleus; their action is extracellular.
4. Step 4: Consider the statement that antibodies are only produced during innate immune responses. This is incorrect because antibody production is a hallmark of the adaptive immune response, not innate immunity.
5. Step 5: Analyze the statement that antibodies directly destroy pathogens by phagocytosis. Antibodies do not perform phagocytosis themselves; instead, they opsonize pathogens to enhance phagocytosis by immune cells.