Answer: A. the Red Beds Plains
Explanation:
The Red Bed Plains is the largest out of 10 geographic regions in Oklahoma and boasts of most of Oklahoma's population as it is the most densely populated region of the state.
There are indeed important oil deposits in some areas and these serve as the main income resource for the region. The region is also blessed with agricultural resources as evidenced by the cotton (which Patty farms), maize, watermelons and sorghum grown in the region.
The source was the land that they owned that they could control the peasants in their feudal system.