Question

which atmospheric gas plays the biggest role in weather and forms clouds? methane water vapor oxygen carbon dioxide

Explanation:

Water vapor is a key component in weather processes. It condenses to form clouds and is involved in precipitation, humidity, and heat - transfer in the atmosphere. Methane is a greenhouse gas but not the main gas for cloud - formation. Oxygen is for respiration and not directly related to cloud - formation or major weather processes. Carbon dioxide is a greenhouse gas but not the primary gas for weather and cloud - formation.

Answer:

B. water vapor