Which physical modification allowed the Mountains and Basins region access to water? need help ASAP!!

The physical modification that allows for water access to the Mountain and Basin region is Dams and Reservoirs.

The Mountains and Basins region:

The region is quite dry but in winter, they get snow and then in spring, they get runoff when the snow melts. Both of these are captured in the many reservoirs and dams built in the region.

The water captured is used judiciously and efficiently to ensure that there is enough for both agricultural and other uses.

In conclusion, dams and reservoirs help people in the Mountain and Basin region to have access to water.

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Dams, down streams and tunnels.

Explanation:

The humans modify the environment to meet their needs. When the humans live near mountains they require water to survive. For this purpose they build dams and down streams from the mountains cutting to flow water to the localities who are dependent on the water for survival.

a.   it resulted in widespread unemployment.