In recent years, there have been many sandstorms and sandstorms in northern China. The main reasons for this phenomenon are () A. The result of global warming B. The atmosphere.

The experimental researchers come to the conclusion that the occurrence of sandstorms is not only the product of specific natural environmental conditions, but also has a corresponding relationship with human activities: human overgrazing, deforestation, industrial and mining traffic construction, especially human overgrazing, destroyed the ground vegetation, disturbed the ground structure, and formed a large area of sandy land, which directly accelerated the formation and development of sandstorms.

So choose: C.