What fundamental change was established by the 16th Amendment?

The 16th Amendment, ratified in 1913, fundamentally established the federal government's ability to impose and collect income taxes without apportioning it among the states or basing it on the U.S. Census. This change significantly altered the financial landscape of the government, allowing it to generate revenue directly from citizens' incomes. Prior to this amendment, income taxes were challenged in courts and were often deemed unconstitutional if not applied uniformly across states. The 16th Amendment streamlined this process, providing a stable source of funding for government operations and facilitating the expansion of social services and infrastructure improvements. The other options refer to different amendments and policies not related to income taxation, such as prohibiting alcohol, ensuring equal protection, and abolishing slavery.