The correct answer to this open question is the following.
The physical characteristics of the Carolinas that influenced settlement patterns and helped rice become a dominant crop were the following.
Carolina is a territory with fertile soil to grow cash crops. So since the very beginning, this attracted many settlers. The climate conditions were good and favored farming. The fact that the Carolinas had large coast and direct connection to the Atlantic Ocean, also was a factor.
Yes, Rice was the most important cash crop in the Lowcountry region. Indeed, Rice was the king of crops in South Carolina for two hundred years.
This factor, the work in the large plantations, and the demand for more and better crops increased the necessity of having more slaves to work in the farm fields.
