What was the primary issue the Missouri Compromise attempted to address?

The primary issue the Missouri Compromise sought to address was slavery. This compromise was enacted in 1820 to help maintain the balance of power between free and slave states as the United States expanded westward. Specifically, it allowed Missouri to enter the Union as a slave state while simultaneously admitting Maine as a free state, thus preserving the equilibrium in Congress between the two factions. Additionally, the compromise established a geographic line along the southern boundary of Missouri, north of which slavery would be prohibited in future states. This was a critical attempt to mitigate the growing tensions between pro-slavery and anti-slavery factions, making it a significant turning point in the debate over slavery in the United States leading up to the Civil War. The other options, while relevant to American history, did not directly address the central conflict surrounding the expansion of slavery into new territories, which was the primary focus of the Missouri Compromise.