Answer:
B: greenhouse
Step-by-step explanation:
Water vapor traps heat in the Earth's atmosphere. This serves to maintain Earth's atmospheric temperature. Based on this function, water can be classified as a greenhouse gas.
Greenhouse gases can be defined as gases that trap heat within the Earth's atmosphere. Thus, an increase in global temperature is largely caused due to an increase in the amount of greenhouse gases in Earth's atmosphere.
Some examples of greenhouse gases present in the atmosphere are methane, water vapor, carbon dioxide etc.