Answer :
Final answer:
The skin acts as a physical and chemical barrier to pathogens by utilizing keratin for resistance, acidity to inhibit pathogen growth, and by trapping pathogens in oil and sweat produced by glands.
Explanation:
The skin protects the body from pathogens by creating a physical and chemical barrier that most pathogens cannot penetrate. This is possible through the presence of keratin, which provides a resistant cover to physical entry, and the acidic nature of the skin, which is hostile to many pathogens. The correct answer to the question is that the skin traps pathogens in oil and sweat produced by glands, though it is important to note that this is just one aspect of the role the skin plays.
Hairs on the body do trap pathogens as well, but the skin's primary defense mechanism includes desiccation (drying out pathogens) and utilizing its acidity. Additionally, the skin is home to beneficial microorganisms that prevent infection by competing with harmful pathogens.