Which of the following is a greenhouse gas?

Carbon dioxide is considered a greenhouse gas because it has the ability to absorb infrared radiation, contributing to the greenhouse effect, which warms the Earth's atmosphere. Greenhouse gases trap heat from the sun in the Earth’s atmosphere, preventing it from escaping back into space. This process is critical for maintaining the planet's temperature within a range that can support life.

In contrast, nitrogen gas, oxygen, and argon do not possess the molecular structure necessary to effectively absorb and emit infrared radiation. Therefore, they do not function as greenhouse gases and do not contribute to the greenhouse effect in the same way that carbon dioxide does.