Answer: Answer is C
Explanation: Considering only the availability of fuel and not the cost of converting it into electricity, fossil fuel will be the most scarce in comparison to wind power, solar energy and hydro-power.
Wind power is abundant since wind will always blow as a result of the kinetic energy produced from the movement of air.
Solar energy is also abundant since the sun will always shine and emit light and heat (at least till billion of years away).
Also, with 71 percent of the earth surface covered with water, water resources are numerous.
However, due to the fact that fossil fuels are natural fuels produced from the decomposition of buried dead organisms, they are considerably finite in comparison to solar, wind and water energy.