Anatomical and physiological barriers provide the crucial first line of defense against pathogens. These barriers include intact skin, vigorous mucociliary clearance mechanisms, low stomach pH and bacteriolytic lysozyme in tears, saliva and other secretions.
White blood cells do. we need a balanced amount of white blood cells to fight off infections!
Answer:
I'm say c it's just a wild guess
I believe that is false, hope this helps