Which of the following can be reduced by the use of renewable energy sources?
a. social costs
b. economic costs
c. environmental costs
d. all of the above

The answer is D. The use of renewable resources can reduce social costs, economic costs and environmental costs. Renewable energy sources like hydropower, solar, wind, biomass and geothermal can provide sustainable energy services since they are available always and are accessible. These sources are known to have less impacts on various aspects especially in the environmental aspect comparing it to nonrenewable resources like fossil fuel based power plants.

D) all of the above 

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