Which cloud type forms in an unstable environment? View Available Hint(s) nimbostratus cumulonimbus cirrus stratus altostratus

In an unstable environment, the cloud type that typically forms is **cumulonimbus**. ### Explanation: - **Cumulonimbus clouds** are associated with thunderstorms and severe weather. They form in conditions where warm, moist air rises rapidly, leading to strong updrafts. This instability in the atmosphere allows for the development of towering clouds that can reach high altitudes. - The other cloud types listed: - **Nimbostratus**: These are thick, gray clouds that cover the sky and bring continuous, steady precipitation. They form in stable conditions. - **Cirrus**: These are high-altitude, wispy clouds that indicate fair weather and do not form in unstable conditions. - **Stratus**: These are low, gray clouds that often cover the entire sky and bring light precipitation, typically forming in stable conditions. - **Altostratus**: These are mid-level clouds that can indicate rain but generally form in stable conditions. Thus, the correct answer is **cumulonimbus**.