The correct option is (c).
Explanation
The atmosphere is a mixture of multiple gases, water vapour, and particulate matter. The proportion of gases changes in the higher layers of the atmosphere, but in the lower atmosphere, the composition is dominated by two specific gases.Statement-wise Analysis:
- Statement 1 is Correct: Nitrogen is the most plentiful gas in the air, comprising approximately 78% of the total volume. It is a crucial constituent for living organisms, particularly for plant growth.
- Statement 2 is Incorrect: The bulk of the atmosphere is constituted by Nitrogen (78%) and Oxygen (21%). Together, these two gases make up about 99% of clean, dry air. Argon (0.93%) and Carbon dioxide (0.036%) represent only a minor fraction of the atmospheric volume.
- Statement 3 is Correct: Gases such as Helium, Hydrogen, Neon, Krypton, and Xenon are present in trace quantities. Their volume is significantly lesser than that of Nitrogen, which is the primary component of the atmosphere.
Key Takeaway: Nitrogen and Oxygen are the dominant gases in the atmosphere, accounting for 99% of its volume, while all other gases, including Argon and Carbon dioxide, exist in minute quantities.