Two sites on the same river have been surveyed as a place to build a dam. The dam will be part of a hydroelectric power plant. Site A is at the top of a 50-meter waterfall. Site B is at the top of a 35-meter waterfall. Which answer correctly describes where the water will have the greater gravitational potential energy to be converted into electricity?

A. Site A
B. Neither site has gravitational potential energy to convert to electricity.
C. Both sites will produce the same amount of electricity as the water flows over the water fall.
D. At both sites the water has the same gravitational potential energy.