Which one of the following gases is not responsible for global warming?

Question: Which one of the following gases is not responsible for global warming?

Water vapor is the most significant greenhouse gas affecting the Earth's temperature. Although carbon dioxide (CO₂) receives much attention due to human emissions, water vapor plays a more crucial role in influencing global warming. CO₂ remains in the atmosphere for up to 1,000 years, while water vapor has a more immediate impact on temperature regulation. Other gases, such as chlorofluorocarbons (CFCs), which have been banned in many parts of the world due to their ozone-depleting effects, have heat-trapping potential thousands of times greater than CO₂. However, their emissions are much lower, so none of these gases trap as much heat as CO₂ does.