Name one regulatory body that oversees water quality in distribution systems.

The Environmental Protection Agency (EPA) plays a crucial role in overseeing water quality in distribution systems across the United States. Established to protect human health and the environment, the EPA sets standards for drinking water quality under the Safe Drinking Water Act. This includes creating regulations that ensure public water systems provide safe drinking water to communities, as well as monitoring and enforcing compliance with these standards. The agency works alongside state and local governments to ensure that drinking water remains safe and free from contaminants, reinforcing its importance as a regulatory body in water distribution.

The other options, while they may sound relevant, do not hold the same authority or recognition in the realm of water quality regulation as the EPA.