Correct Option
The correct option is A-2, B-4, C-1, D-3
Explanation
The atmosphere is a mixture of gases that surrounds the Earth. The primary components include Nitrogen and Oxygen, which make up the bulk of the air, along with trace amounts of Argon, Carbon Dioxide, Water Vapour, and other gases. Each constituent plays a distinct role in ecological and physical processes.
Statement-wise Analysis
- A. Nitrogen (Matches 2): Nitrogen is the most abundant gas in the atmosphere, constituting approximately 78% by volume. It is relatively inert and does not support combustion (burning). Its presence dilutes the activity of oxygen, preventing rapid and uncontrollable combustion.
- B. Oxygen (Matches 4): Oxygen makes up about 21% of the atmosphere. It is essential for the survival of most living organisms (respiration) and is a necessary supporter of combustion (burning).
- C. Water Vapour (Matches 1): Water vapour is the gaseous state of water in the atmosphere. It is the fundamental component of the hydrological (water) cycle, facilitating processes such as evaporation, condensation, and precipitation.
- D. Carbon Dioxide (Matches 3): Carbon Dioxide is produced during respiration and the burning of fossil fuels. While essential for photosynthesis, high concentrations in confined spaces can displace oxygen, leading to suffocation. It is also a major greenhouse gas.
Key Takeaway
Nitrogen is the most abundant gas and inhibits burning; Oxygen supports life and combustion; Water Vapour drives the water cycle; and Carbon Dioxide is a product of combustion and respiration.