Which of the following is a component of the immune system that helps protect the body from diseases?

• A. Alveoli
• B. Nephrons
• C. Lymphocytes
• D. Osteocytes

Answer: (C)

Verified step by step guidance

1. Step 1: Begin by understanding the immune system's role in protecting the body from diseases. The immune system is composed of various cells, tissues, and organs that work together to identify and eliminate pathogens such as bacteria, viruses, and other harmful agents.
2. Step 2: Review the function of each term provided in the options: Alveoli are tiny air sacs in the lungs responsible for gas exchange during respiration, not directly involved in immunity. Nephrons are the functional units of the kidney responsible for filtering blood and forming urine, also not part of the immune system. Osteocytes are mature bone cells that maintain bone tissue, unrelated to immune defense.
3. Step 3: Focus on lymphocytes, which are a type of white blood cell and a key component of the immune system. Lymphocytes include B cells, T cells, and natural killer (NK) cells, all of which play critical roles in identifying and neutralizing pathogens.
4. Step 4: Understand the specific roles of lymphocytes: B cells produce antibodies to target specific antigens, T cells help destroy infected cells and coordinate immune responses, and NK cells attack cells infected by viruses or cancerous cells.
5. Step 5: Conclude that lymphocytes are the correct answer because they are directly involved in the immune system's function to protect the body from diseases, unlike the other options provided.