What invention most to make the shift to large plantations throughout the deep south profitable? a. the textile mill b. the mechanical reaper c. the cotton gin d. the sewing machine

The invention of the cotton gin (C) in 1793 made the shift to large plantations throughout the Deep South profitable. The cotton gin allowed for the quick separation of cotton from their seeds allowing for a faster rate of harvesting the crops. This led to increased development of agriculture in the American South as well as the rise in the slave trade. 

The cotton gin. It produced more cotton faster, and more items were cheaper, so it helped shift large plantations throughout the Deep South so it was profitable.