The most accurate response regarding how the changes shown on the maps impacted the United States is: They increased sectionalism by disrupting the balance between free and slave-holding states.
This statement reflects the historical context of how various territorial expansions and changes in state designations affected the delicate balance between free and slave states, intensifying tensions that ultimately contributed to the Civil War. Other options may involve valid points but do not directly address the core issue of sectional conflict related to slavery that was a significant factor during this period in American history.