I want to test the ability of students to read a passage and answer questions about it. Could you please come up with a good question for the passage "The Alps provide lowland Europe with drinking water, irrigation, and hydroelectric power. Although the area is only about 11 percent of the surface area of Europe, the Alps provide up to 90 percent of water to lowland Europe, particularly to arid areas and during the summer months. Cities such as Milan depend on 80 percent of water from Alpine runoff. Water from the rivers is used in over 500 hydroelectricity power plants, generating as much as 2900 kilowatts of electricity."? 

What energy source do the Alps do for parts of Europe?