Answer:
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:
The answer is D. Water
Please mark me brainliest
1) Wrestling.
Explanation: Wrestling has been around for millions of years, Wrestling is something that comes along almsot everyday. Kid's wrestle(play fight), adults do too. Which makes it common. Also wrestling has been around for over 15,000 years!
2) Running.
Explanation: Running is very common, we all run daily which makes running common. Also running has been around for millions of years. Even dinosaurs ran. So that being said, running is one of the oldest competitive sports.
Both of these are both very competitive. either to win money or take home a trophy.
Millions of people compete for a title. Which makes them competitive.