Answer: Option (D) is correct.
Step-by-step explanation:
Missouri Compromise of 1820 is referred as the legislation which provided for Maine admission to US as a free state alongside Missouri as a slave state, therefore maintaining the equilibrium of authority between North and South in US Senate. The 16th US Congress passed this legislation on 3rd March 1820, and the President at that time James Monroe ratified it on 6th March, 1820.