Answer:
The change in the U.S. Constitution shown in these excerpts reflects an attempt to strengthen the principle of popular sovereignty. The 17th Amendment, which changed the method of selecting Senators from being chosen by state legislatures to being elected by the people, was a significant expansion of democracy and gave citizens a more direct say in the selection of their representatives. This change reflects a belief in the importance of popular sovereignty, or the idea that the people are the ultimate source of political power.