What is a critical role of the immune system?

• A. Support the muscular system
• B. Control the respiratory rate
• C. Protect against pathogens
• D. Maintain bone density

Answer: (C)

The immune system plays a crucial role in protecting the body against pathogens, which include bacteria, viruses, fungi, and other harmful microorganisms. This protection is achieved through various components of the immune system, including white blood cells, antibodies, and the lymphatic system. When the body encounters a pathogen, the immune system is activated to identify, attack, and eliminate the threat, effectively preventing infections and supporting overall health.

This role is fundamental because the effectiveness of the immune system directly influences the body's ability to fend off diseases and maintain homeostasis. If the immune response is compromised or malfunctioning, individuals become more susceptible to infections and diseases, which can lead to more serious health issues. The other options do not pertain to the primary function of the immune system, highlighting the specificity and importance of immune defense.