Final answer:
The combination of elevation, steep-sided valleys, and steady flowing rivers are ideal conditions for the production of Hydroelectric power. This is due to the gravity-driven water flow which is harnessed to generate electricity.
Step-by-step explanation:
The combination of elevation, steep-sided valleys, and steady flowing rivers provides ideal conditions for the production of Hydroelectric power (C). Hydroelectric power plants harness the energy created by gravity-driven water flow to generate electricity. These conditions are especially prevalent in areas of high elevation where rainwater and melting snow feed constant, strong river flows. The steep valleys facilitate the formation of dams and reservoirs, which are integral components of a hydroelectric power system.
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