Final answer:
The second compromise of the Missouri Compromise stated that Free African-American citizens could not enter Missouri, as per answer choice A. This was part of the broader Missouri Compromise which admitted Missouri as a slave state and Maine as a free state, with a dividing line at 36°30' for future territories from the Louisiana Purchase.
Step-by-step explanation:
The Missouri Compromise was a significant legislative agreement in the history of the United States that addressed the balance of slave and free states.
In response to the question about the second compromise of the Missouri Compromise, the correct answer is A) Free African-American citizens could not enter Missouri. Although legislators agreed that this ban violated the Constitution, they reaffirmed Missouri's ability to deny citizenship to African American citizens.
The Compromise involved the admission of Missouri as a slave state and Maine as a free state, maintaining the balance in the Senate. A key part of the Compromise was the establishment of the 36°30' line as a division between slave and free territories in the Louisiana Purchase.
The proposal by James Tallmadge to prohibit the importation of enslaved people to Missouri and to free enslaved children born in Missouri at age twenty-five was rejected, as it represented a significant challenge to the pro-slavery standing of southern states.