What pre-civil war arrangement guaranteed that new states entering the nation would keep the balance between slave and free states?

select one:
a. mason-dixon line
b. bloody kansas
c. us constitution
d. missouri compromise

d. Missouri Compromise

The Missouri Compromise is an agreement that guaranteed balance between slave and Free states. In 1819, Missouri was asked to enter the Union as a slave state but a bitter debate arose that was not resolved only after Maine requested entry as a free state in 1820. The Congress battle to have an equal number of slave states and Free states.

However, the Missouri Compromise became controversial for many had worried that the country had become lawfully divided along sectional lines, so the bill was effectively repealed as Kansas-Nebraska Act of 1854 and declared unconstitutional that resulted to increase tensions over slavery and eventually led to the civil war.

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