How much percentage of oxygen is present in the atmosphere?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 21%.
Oxygen constitutes approximately 21 percent of the Earth's atmosphere by volume. This proportion is vital for the respiration of most living organisms and plays a crucial role in various atmospheric processes, including the formation of the ozone layer. The remaining composition of the atmosphere primarily includes nitrogen (about 78 percent) and trace gases such as argon, carbon dioxide, and others. The balance of these gases is essential for maintaining the planet's climate and supporting life.