Which one of the following is an example of renewable energy ?
Hydroelectric
Renewable energy comes from sources that are naturally replenished on a human time scale, such as sunlight, wind, flowing water, biomass and geothermal heat.
Hydroelectric power uses the energy of water flowing from a height. The water is continually replenished by the solar-driven water cycle of evaporation and rainfall, so hydropower is renewable.
Natural gas and petroleum oil are fossil fuels formed over millions of years and are depleted as they are used. Nuclear power depends on mined uranium ore, which is a finite resource, so it is also classed as non-renewable.
So the renewable source among those listed is hydroelectric power.
Hence, Hydroelectric.