The immune system is a matrix of organs and cells charged with

The immune system is a matrix of organs and cells charged with

• A. Limiting infection
• B. Killing invading microorganisms
• C. Clearing pathogens and infected cells
• D. All of the above

Answer: (D)

The immune system protects the body by both containing infections and actively eliminating invaders, and by clearing pathogens and the cells that infection damages. It acts quickly through innate defenses to limit infection and kill microbes, and it uses adaptive defenses to target specific pathogens and remove infected cells and debris with antibodies and cytotoxic cells. Because each of these roles—limiting infection, killing invading microorganisms, and clearing pathogens and infected cells—are essential parts of how the immune system works, the option that includes all of them best captures its full function.

The immune system protects the body by both containing infections and actively eliminating invaders, and by clearing pathogens and the cells that infection damages. It acts quickly through innate defenses to limit infection and kill microbes, and it uses adaptive defenses to target specific pathogens and remove infected cells and debris with antibodies and cytotoxic cells. Because each of these roles—limiting infection, killing invading microorganisms, and clearing pathogens and infected cells—are essential parts of how the immune system works, the option that includes all of them best captures its full function.