Which statement best describes active immunity?

Which statement best describes active immunity?

• A. Stimulates antibody production
• B. Appears following exposure to an antigen
• C. Is a direct result of an immune response
• D. All of the above

Answer: (D)

Active immunity is produced by the body's own immune system in response to an antigen. When exposure occurs, the immune system activates B cells to produce antibodies and creates memory cells for faster responses in the future. Because these features—antibody production, occurrence after antigen exposure, and being a direct product of the immune response—are all true, all of the above statements describe active immunity.

Active immunity is produced by the body's own immune system in response to an antigen. When exposure occurs, the immune system activates B cells to produce antibodies and creates memory cells for faster responses in the future. Because these features—antibody production, occurrence after antigen exposure, and being a direct product of the immune response—are all true, all of the above statements describe active immunity.