What statement best highlights why the south-central region was over-farmed contributing to the dust bowl?

The Dust Bowl endured about 10 years. Its essential zone of effect was on the southern Plains. The northern Plains were not so gravely affected, but rather regardless, the dry spell, windblown tidy and farming decay were no outsiders toward the north. 
Below are the statements:
- the interest for grain developed amid WWI 
- rich soil in the region delivered astounding products 
- The Homestead Act urged pilgrims to guarantee arrive