Answer:
Option D, Nimbostratus
Explanation:
Nimbostratus clouds are low lying clouds usually found at height of some 6000 to 7000 feet from ground. They are formed from the altostratus cloud after they get thick and dark.
The color of these clouds vary from dark grey to black due to water contained in it. They can cause persistent rain (for several hours) and in cold weather they may also cause snow/icy precipitation.
Thus, option D is correct.
