Question

an individual was exposed to a contagious disease but did not become infected. the agent was unable to enter the body and grow because it was stopped by the persons skin. this is an example of how a ____________ can prevent disease.
a. chemical barrier
b. physical barrier
c. protective behavior
d. medication
please select the best answer from the choices provided.

Explanation:

The skin is a physical structure that blocks the entry of the disease - causing agent. It is not a chemical barrier (which would involve substances like enzymes or antibodies), not a result of protective behavior (which would be actions like wearing a mask or washing hands), and not medication (which is a substance taken to treat or prevent disease).

Answer:

B. physical barrier