Buy cars that use gasoline. Build power plants that use coal. Use renewable resources to generate power. Use nonrenewable resources to generate power.
I gave my students this multiple choice question: As the human population increases, more fossil fuels are being used. The burning of fossil fuels produces greenhouse gases. How might humans reduce greenhouse gases?

Only one answer is correct among these 4 choices:
- Buy cars that use gasoline.
- Build power plants that use coal.
- Use renewable resources to generate power.
- Use nonrenewable resources to generate power.

Could you tell me which one is correct?

Use renewable resources to generate power.