In which year did the Central Arizona Project begin operation?

The Central Arizona Project began operation in 1973. However, to understand the relevance of the dates provided in the multiple-choice options, it's important to acknowledge that the project has had various phases and developments over the years.

The Central Arizona Project is a major water supply system that conveys water from the Colorado River to central and southern Arizona. It was created to address the water demands of the region, and significant portions of the project were completed and began to supply water effectively during the years following its initial construction.

While the options suggest the late 1980s to early 2000s as starting points for operation activities, the most notable expansion and operational milestones happened around that time but were initially established earlier. Therefore, while the selected year might resonate with certain operational phases or achievements, the Central Arizona Project's primary operations began in the earlier year of 1973.