Answer:
B. gravitational potential energy
Explanation:
If we talk about gravitational potential energy, it is the energy that a body or object possess due to its certain position in a gravitational field.
This energy is commonly used by an object that is present near the earth surface where the value of gravitational acceleration is around 9.8 m/s2.
If we talk about a hydroelectric power plant, where water is stored high above a turbine, it means it is at a certain height from the earth. Because water is stored high above a turbine but is starts to fall due to gravitational energy (GPE) towards the earth. When water falls this gravitational potential energy is converted into kinetic energy that moves the turbine. When the turbine moves, generator that is connected to it converts kinetic energy into electrical energy.
Thus the energy that is triggering the whole process is GPE, that is is why the most appropriate option is B: gravitational potential energy.
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