What percentage of the atmosphere is composed of nitrogen?

The correct percentage of the atmosphere composed of nitrogen is approximately 78 percent. Nitrogen is the most abundant gas in Earth's atmosphere, making up this significant portion. This abundance is critical for various processes, including the nitrogen cycle, which is essential for life. Nitrogen is relatively inert and does not readily react with other elements, contributing to its stability in the atmosphere.

While oxygen constitutes about 21 percent of the atmosphere, the other options represent gases that occur in much smaller quantities or are far from the actual composition of the atmosphere. Understanding the composition of the atmosphere is important for various fields, including meteorology and aviation, as it affects air density, flight performance, and weather patterns.