The correct answer is B.
Cumulus congestus are towering cumulus clouds that are dense and have a cauliflower-like appearance. They are often associated with thunderstorms and other severe weather.
Option A is a cumulus cloud. Cumulus clouds are puffy, white clouds that are typically found at low altitudes. They are formed when warm, moist air rises and cools, causing the water vapor to condense into clouds.
Option C is a stratocumulus cloud. Stratocumulus clouds are low, gray clouds that are often found in layers. They are formed when warm, moist air rises and cools, causing the water vapor to condense into clouds.
Option D is a cirrus cloud. Cirrus clouds are thin, wispy clouds that are made of ice crystals. They are typically found at high altitudes.
Cumulus congestus clouds are often mistaken for cumulonimbus clouds, which are thunderstorm clouds. However, cumulonimbus clouds are much taller and have a more anvil-shaped appearance.