They make waste products. They are buried far underground. They take a very long time to produce. They are more expensive than nuclear fuels.
I gave my students this multiple choice question: Why are fossil fuels called nonrenewable resources?

Only one answer is correct among these 4 choices:
- They make waste products.
- They are buried far underground.
- They take a very long time to produce.
- They are more expensive than nuclear fuels.

Could you tell me which one is correct?

They take a very long time to produce.