A belief by southern businessmen that the southern economy should focus on the export of select agricultural products is the following statement most directly contributed to the development described in the excerpt.
Slavery was so lucrative that the Mississippi River valley produced more millionaires per capita than any other region of the country. With cash crops like tobacco, cotton, and sugar cane, the southern states of America developed into the country's economic engine. Cotton became the Deep South's cash crop after the cotton gin was created, which fueled a rise in the need for enslaved people from the Upper South to work the land. Crops could be grown more successfully in the South due to its climate and soil. Cash crops were produced in such large numbers that a plantation owner needed as many people as possible to gather as much of the crop as possible each day, necessitating the use of slave labour.
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