The most abundant gas in Earth's atmosphere is nitrogen. Therefore, the correct answer is b. Nitrogen.
The most abundant gas in Earth's atmosphere is nitrogen. To determine the answer to this question, you can refer to scientific resources or conduct a quick search online. By doing so, you will find that nitrogen makes up about 78% of the Earth's atmosphere, while oxygen is the second most abundant gas at approximately 21%. Carbon monoxide and carbon dioxide are present in much smaller quantities.
