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

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.

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The person who utilize the progression principle will keep adding the difficulty of the exercise that he's doing, while the person who does not, will only stay stagnant.  the person that utilize progression principle, will get a stronger endurance because now his body is conditioned to do harsher routines.{the answer was already on verified)