Which of the following best illustrates artificially acquired active humoral immunity?

• A. Receiving a vaccine containing inactivated pathogens
• B. Receiving antibodies from another individual via injection
• C. Transferring maternal antibodies to a newborn through breast milk
• D. Developing immunity after recovering from a natural infection

Answer: (A)

Verified step by step guidance

1. Understand the key terms: 'artificially acquired' means immunity gained through deliberate medical intervention, 'active' means the immune system produces its own antibodies, and 'humoral immunity' involves antibodies circulating in body fluids.
2. Analyze each option to see if it fits these criteria: whether the immunity is artificially induced, whether the body actively produces antibodies, and whether it involves humoral (antibody-mediated) immunity.
3. Option 1: Receiving a vaccine containing inactivated pathogens involves deliberate introduction of antigens to stimulate the body's own antibody production, fitting artificially acquired active humoral immunity.
4. Option 2: Receiving antibodies from another individual via injection is artificial but passive immunity because antibodies are transferred directly, not produced by the recipient's immune system.
5. Option 3 and 4 involve natural acquisition of immunity (passive through breast milk and active through infection), so they do not represent artificially acquired active humoral immunity.