Which of the following is a nonrenewable resource?

• A. Solar energy
• B. Wind energy
• C. Coal
• D. Hydroelectric power

Answer: (C)

Nonrenewable resources are those that form far more slowly than they are consumed, on timescales of millions of years. Coal fits this because it originated from ancient plant material buried and transformed underground for a very long time. Once mined and burned for energy, there isn’t a quick way to replace the coal we have used. The other options come from sources that are continuously renewed: solar energy from the sun, wind energy from atmospheric movement, and hydroelectric power from the ongoing water cycle. So coal is the nonrenewable choice.