Why are the turbine for hydroelectric dams located far below the top of the dam?

Question

1. To allow the kinetic energy of the water to increase greatly before reaching the turbines
2. To allow the potential energy of the water to increase greatly before reaching the turbines
3. To ensure that the water does not lose too much potential energy before reaching the turbines
4. To ensure that the water does not lose too much kinetic energy before reaching the turbines

Answer 1

3. To ensure that the water does not lose too much potential energy before reaching the turbines