The best assessment of how the Sixteenth Amendment has increased the power of the national government is:
C. The Sixteenth Amendment has allowed the national government to make policy in areas that are traditionally reserved to the states.
The Sixteenth Amendment, ratified in 1913, grants Congress the power to impose and collect income taxes without apportioning it among the states or basing it on the U.S. Census. This ability to levy income tax has provided the federal government with significant financial resources, which in turn has allowed it to expand its influence and role in various policy areas that were traditionally managed by state governments.