What were the two basic causes of the Dust Bowl during the early 1930s? strip mining and toxic chemical dumping over farming and drought urban sprawl and overpopulation deforestation and railway construction

Severe drought and failure to apply dryland farming methods to prevent wind erosion were the reasons for the Dust Bowl.

So the correct answer would be toxic chemical dumping over farms and drought urban sprawl.

B: "over farming and drought"

Good luck on summer school! I'm nearly done myself.