Answer:
A. Indian tribes had more area to move into as settlers pushed them
out.
Explanation:
Through the Louisiana Purchase the United States acquired an area more than 828,000 square miles, doubled the size of the United States and opened up the continent to its westward expansion and also provided access to the Mississippi River .
Extreme pro-slavery elements objected to it because it provided a precedent by which Congress had power to regulate slavery. Abolitionists opposed it because it allowed slavery to continue to spread in some of the areas.