Which river are Arizona, Nevada, and Mexico getting less water from due to droughts?

The Colorado River is the correct answer because it is a critical water source for several southwestern states, including Arizona and Nevada, as well as for Mexico. Over the past few decades, the region has experienced significant drought conditions, which have led to a reduction in the river's flow. This decrease in water availability has serious implications for agriculture, drinking water supplies, and the overall ecosystem in the areas dependent on the Colorado River.

The river's overall water supply has been strained due to increasing demand from growing populations and agricultural use, coupled with the long-term effects of climate change, which exacerbate drought conditions. As water levels in reservoirs fed by the Colorado River, such as Lake Mead and Lake Powell, continue to drop, it further highlights the challenges faced by these states and Mexico in managing their water resources effectively.

In contrast, the other rivers mentioned do not have the same direct impact on Arizona, Nevada, and Mexico, making the Colorado River the most relevant choice in this context.