Which act was authorized by Congress in 1966 to deliver Colorado River water to Arizona?

The Central Arizona Project is the correct choice because it was specifically authorized by Congress to provide a reliable water supply from the Colorado River to central and southern Arizona. Established in the Colorado River Basin Project Act of 1968, its intention was to facilitate the delivery of water to areas that previously lacked adequate supplies, thereby supporting agricultural activities and urban growth in Arizona. The project involves a system of aqueducts, which transport water from the Colorado River to various parts of the state, making it crucial for the state's water management and planning.

The other acts mentioned do not pertain to the delivery of Colorado River water to Arizona: the California Environmental Quality Act addresses environmental protection and regulation in California; the Wild and Scenic Rivers Act focuses on the preservation of certain rivers in their free-flowing condition; and the Safe Drinking Water Act sets standards for drinking water quality but does not involve infrastructure for water delivery.