Which law was established to reduce the discharge of pollutants into US waters?

The Clean Water Act is the correct choice because it was specifically designed to address the quality of the nation's waters by regulating the discharge of pollutants. Established in 1972, its primary aim is to restore and maintain the integrity of the waters by ensuring that they are safe for fishing, swimming, and other recreational activities. The Act provides the framework for regulating discharges of pollutants from point sources, establishing water quality standards, and supporting pollution control programs.

In contrast, the Clean Air Act focuses on air quality and the regulation of air pollutants, while the Safe Drinking Water Act is aimed at ensuring safe drinking water supplies. The Environmental Protection Agency Act, although foundational, primarily established the EPA and its overarching responsibilities without directly regulating water pollution in the same manner as the Clean Water Act. Hence, the Clean Water Act stands out as the specific legislation aimed at reducing water pollution in the United States.