The American Dust Bowl Was Caused by All of the Following

Multiple Choice

The American Dust Bowl was caused by all of the following except:

A) the fact that the Great Plains of North America have low annual precipitation.
B) the extensive removal of native prairie grasses to plant crops.
C) overgrazing.
D) unusually severe wind and storm conditions.
E) the poor (nutrient) quality of the soil of the Great Plains.