What explains why there is usually lush vegetation on one side of the mountain and a dry, desert-like climate on the other side? A) lower levels of sunlight on the windward side of the mountain B) higher levels of pollution on the leeward side of the mountain C) lower levels of nutrients on the windward side of the mountain D) lower levels of precipitation due to a rain shadow on the leeward side of the mountain

D) lower levels of precipitation due to a rain shadow on the leeward side of the mountain.

Explanation:

Mountains stop rainy whether at one side of the mountain which results in lush vegetation on that side and results in the rain shadow on another side.  

Rain shadow is that patch of land which is dry and warm because of lower level of precipitation as a result of blockage of rainy weather in opposite site by mountains. This side is called the leeward side. Dry warm climate is present at this site.

Example of rain shadow is dry basins east of the Cascade Range, The Great Basin of Nevada and Utah. These are found in North America. So the correct answer is D.

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