Which of the following is a nonrenewable energy resource?

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

Answer: (B)

Nonrenewable resources are those that exist in finite amounts or form very slowly over geological timescales, so they cannot be replenished on human timeframes. Coal is a fossil fuel created from ancient plant matter that was buried and transformed over millions of years; once mined and burned, the usable supply diminishes with no quick way to replace it. The other options rely on ongoing natural processes: solar energy comes from the sun, wind is driven by atmospheric conditions powered by solar heating, and hydroelectric power uses the continuous water cycle. These processes provide energy that can be replenished relatively quickly, making them renewable.