B Heavy snow and rain.
Altocumulus and altostratus clouds are mid level clouds. Altocumulus clouds are made up of water droplets. They are appear as gray and puffy mass. They are formed in groups. These clouds are responsible for causing thunderstorm. Altostratus clouds consists of ice crystals and water droplets. These clouds are gray or blue gray in color. These clouds usually cover the whole sky. These clouds are responsible for causing continuous rain or snow.
Both of these clouds exert almost similar influence on the weather condition of the region. Hence, these clouds usually brings heavy snow and rain.
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