In what year was the Safe Drinking Water Act enacted?

The Safe Drinking Water Act was enacted in 1974, making this the correct answer. This significant piece of legislation was established to protect public health by regulating the nation's public drinking water supply. The act aimed to ensure that municipalities and water systems provide safe drinking water to the public. It set standards for water quality and helped establish a comprehensive framework for the management and safeguarding of drinking water.

The dates provided by the other choices do not correspond to the enactment of this critical legislation. While earlier and later dates relate to various other environmental regulations or amendments to existing laws, none address the establishment of the Safe Drinking Water Act itself, which has played a pivotal role in water safety and public health in the United States since its passage.