The correct option is (c).
Explanation
The Earth's atmosphere is a mixture of various gases, water vapour, and dust particles. The proportion of gases changes in the higher layers of the atmosphere, but in the lower atmosphere (homosphere), the composition of clean, dry air remains relatively constant.- Statement 1 is Correct: Nitrogen and Oxygen are the two major permanent gases in the atmosphere. Nitrogen accounts for approximately 78.08% and Oxygen accounts for approximately 20.95% by volume. Together, they constitute roughly 99% of the total volume of clean, dry air.
- Statement 2 is Incorrect: Argon is the third most abundant gas, constituting approximately 0.93%, and Carbon Dioxide constitutes about 0.036% (variable). The combined volume of Argon and Carbon Dioxide is less than 1%, which is significantly lower than the stated 10%.
- Statement 3 is Correct: Oxygen is chemically active and essential for respiration in living organisms and for combustion processes. Due to its critical role in sustaining life, it is metaphorically and biologically referred to as the "breath of life."
Key Takeaway: The atmosphere is dominated by Nitrogen and Oxygen (99%), while Argon (0.93%) and Carbon Dioxide (0.036%) are minor constituents, despite the latter's significance in the greenhouse effect.