How Had American Farmers in the Great Plains Contributed to the Environmental

How had American farmers in the Great Plains contributed to the environmental disaster of the Dust Bowl?

A) Their aggressive farming practices had stripped the landscape of its natural vegetation.
B) They had employed excessive amounts of new, poisonous fertilizers that were the product of the new chemical industry.
C) They had watered the bare soil too aggressively, which led to run-offs and uneven fields.
D) They had largely depended on the wrong crop for the region, focusing on corn instead of cotton.