What is the main geographical problem facing Nevada, Arizona, and Colorado in recent years?

The main geographical problem facing Nevada, Arizona, and Colorado in recent years is indeed drought, particularly impacting vital water sources such as Lake Mead and Lake Powell. These regions rely heavily on these reservoirs for water supply, which is vital for municipal use, agriculture, and recreation. Persistent drought conditions have significantly lowered the water levels in these lakes, leading to a water crisis that affects not only the population but also environmental sustainability in the area.

The reduction in water availability can lead to various socio-economic consequences, including limitations on agricultural output and increased competition for water resources among different users. Furthermore, as the climate continues to change, the likelihood of drought conditions intensifying makes this issue increasingly critical for the states involved. Addressing this problem requires careful water management and conservation efforts as well as long-term planning to adapt to changing environmental conditions.

The other options do not accurately reflect the pressing challenges these states currently face. Flooding is not a dominant concern for these arid regions, urban sprawl, while a significant issue, does not compare in immediacy and impact to the ongoing drought crisis, and deforestation is not as prevalent or problematic as water scarcity influenced by drought in these specific states.