Which preparation is used to activate an immune response to provide acquired immunity?

• A. Immunoglobulin
• B. Antigen
• C. Vaccine
• D. Serum

Answer: (C)

The correct choice of vaccine is essential because it is specifically designed to activate an immune response and provide acquired immunity against certain diseases. Vaccines contain antigens that mimic a pathogen, which stimulates the immune system to recognize and combat similar infections in the future. When a vaccine is administered, the body produces an immune response, including the generation of memory cells that remember how to fight the pathogen should the individual be exposed to it later on.

In contrast, immunoglobulins are antibodies produced by the immune system in response to antigens. While they play a role in protecting against infections, they do not activate an immune response as vaccines do. Antigens are substances that provoke an immune response but do not serve as a preparation for the purpose of vaccination. Serum typically contains antibodies but does not activate the immune system in the way that vaccines do, as it is usually used for passive immunity rather than acquired immunity. Thus, the vaccine stands out as the preparation specifically created to generate an active immune response and establish long-lasting immunity.