Consider the following characteristics of a cloud type : 1. They are born through convection. 2. Only cloud type that can produce hail, thunder and lightning. 3. They are large cauliflower-shaped towers, often with 'anvil tops'. Identify the type of cloud on the basis of the given characteristics.

The correct answer is B, Cumulonimbus. Cumulonimbus clouds form by strong convection, grow into huge cauliflower-like towers with flat anvil-shaped tops, and are the only clouds that bring hail, thunder and lightning. When the ground heats up, warm moist air rises fast, cools and condenses into a cumulus cloud. If the rising continues, the cloud can grow from near the ground to the top of the troposphere, about 12 to 15 km high, where strong winds flatten its top into an anvil. Inside, rising and falling currents carry ice and water up and down, building hailstones and separating electric charge, which causes lightning and thunder. Such clouds bring the afternoon thunderstorms of the tropics and the pre-monsoon storms of India. Option A is wrong because stratocumulus are low, lumpy grey layers that give at most light drizzle. Option C is wrong because cirrocumulus are high, thin, small white patches of ice crystals that give no rain. Option D is wrong because nimbostratus are thick grey layers giving steady rain, not hail or lightning. Exam tip: nimbo means rain; cumulonimbus is the thunderstorm cloud with an anvil top.