Answer the following question: Answer the following question given this paragraph: Mechanical barriers physically block pathogens from entering the body. The skin is the most important mechanical barrier. In fact, it is the single most important defense the body has. The outer layer of the skin is tough and very difficult for pathogens to penetrate. Q: What type of barrier physically blocks pathogens from entering the body? A:

Select from the following.
a). Solid
b). potential
c). molecular
d). mechanical
Answer:
d).