Answer:
The correct answer is D. The Northwest Ordinance established the procedure by which the United States would expand westward across North America by the admission of new states, rather than by the expansion of existing states.
Step-by-step explanation:
The Northwest Ordinance of July 14, 1787 was a law passed by the Congress of the Confederation of the United States with the main objective of establishing the Northwest Territory. This became the first federally governed territory of the United States outside the area south of the Great Lakes, north and west of the Ohio, and east of the Mississippi. On August 7, 1789, the American Congress ratified the ordinance.
In addition to the American Declaration of Independence, this regulation was the most important legislative act adopted by members of the Continental Congress. The Ordinance created a precedent regarding the western expansion of the United States through the creation of new territories and states instead of enlarging existing states. Furthermore, the prohibition of slavery in the territory made the Ohio River the border between free and slave territory in the area between the Appalachians and the Mississippi. This division brought the possibility for an arrangement between free and slave states that formed the basis for the most important political issue in American politics of the nineteenth century before the Civil War.