Which of the following was a human geographic factor that affected the Dust Bowl?

One major factor of the creation of the Dust Bowl was due to the climate, which was lack of rainfall and unnaturally hot weather. Another reason for the Dust Bowl was the fact that farmers were reusing the same land, causing to it lose nutrients and become dry. Also, due to World War I, farmers were forced to over produce crop, also causing a loss of nutrients in the soil.