The correct answer is C. Nitrogen.
Nitrogen is the most abundant gas in the Earth’s atmosphere, making up about 78% of the total volume. It is a colorless, odorless, and tasteless gas that is essential for life. Nitrogen is used by plants to create proteins and other essential molecules, and it is also used by animals to breathe.
Carbon dioxide is the second most abundant gas in the atmosphere, making up about 21% of the total volume. It is a colorless, odorless, and tasteless gas that is produced by the respiration of animals and the decay of organic matter. Carbon dioxide is also released into the atmosphere when fossil fuels are burned.
Ozone is a gas that is formed when oxygen molecules are split by ultraviolet radiation. Ozone is found in the stratosphere, where it protects life on Earth by absorbing harmful ultraviolet radiation. Ozone is also found in the troposphere, where it is a major component of smog.
Neon is a noble gas that is found in the Earth’s atmosphere in very small amounts. It is a colorless, odorless, and tasteless gas that is used in neon signs and other lighting applications.
In conclusion, the correct answer is C. Nitrogen.