Final answer:
Eli Whitney's cotton gin invention made cotton profitable and led to the cementation of slavery in the Southern economy.
Step-by-step explanation:
The invention that made cotton profitable and led to Slavery becoming cemented in the Southern economy was Eli Whitney's cotton gin. The cotton gin improved the efficiency of cotton production by removing the seeds quickly, allowing for faster production of cotton. This led to an increase in cotton production and made it a more profitable cash crop for the South.
With the rise of cotton production, the demand for enslaved labor also increased. Slavery became integral to the Southern economy as plantation owners relied on enslaved people to harvest and process the cotton. The profitability of cotton and the dependence on enslaved labor contributed to the entrenchment of slavery in the Southern economy.
By the mid-19th century, the cotton industry and slavery had become tightly intertwined, and any attempts to challenge or change the institution of slavery were met with resistance. This connection between cotton, slavery, and the Southern economy played a significant role in shaping the history of the United States.