Larry is taking a walk in the park
the pollen in the air makes him sneeze constantly.
what line of defense is his immune system exhibiting?

Larry is taking a walk in the park. The pollen in the air makes him sneeze constantly. The line of defense that is his immune system exhibiting is that of "first line of defense." There are only 3 lines of defense in the immune system. The first line of defense are a combination of physical and chemical barriers that prevent all types of foreign agents from penetrating the outer layer of the body. In this case, it is the nasal cavity.

Explanation:

not really sure sorry just trying to get points

i think it's the first one because doctors aren't the ones who get rid of the old needles. most of them time it's not even doctors who give you shots, it's nurses.