Which cloud type is developed in an unstable environment aloft and can extend to vast altitude?

• A. Developed in an unstable environment aloft and can extend to vast altitude
• B. Turbulence
• C. The cloud will form
• D. A cloud will form

Answer: (A)

Vertical development of clouds is driven by atmospheric instability. When the air is unstable, parcels rise freely, cool, and condense moisture, feeding the growth of tall clouds. If the updrafts are strong, this growth continues upward from near the surface to very high levels, producing cumulonimbus clouds. These are the cloud types that can reach great altitudes and are often associated with thunderstorms and severe weather. The described idea—developing in an unstable environment aloft and extending to vast height—best matches cumulonimbus, which is why that option is the correct one. The other choices refer to turbulence or generic formation statements and don’t identify the cloud type or its characteristic vertical extent.