An example of fossil fuel is

Options

A. Wood
B. Animal waste
C. Coal
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Fossil Fuels**: Fossil fuels are natural substances formed from the remains of ancient plants and animals that have been buried and subjected to heat and pressure over millions of years. Common examples include coal, oil, and natural gas.

2. **Evaluating the Options**: The question provides four options: wood, animal waste, coal, and all of these. We need to determine which of these qualifies as a fossil fuel.

3. **Analyzing Each Option**:
- **Wood**: Wood comes from trees and is a renewable resource. It does not undergo the same geological processes as fossil fuels, so it is not considered a fossil fuel.
- **Animal Waste**: While animal waste can decompose, it does not undergo the long-term geological processes required to form fossil fuels. Therefore, it is not classified as a fossil fuel.
- **Coal**: Coal is formed from the remains of ancient plants that were buried and subjected to heat and pressure over millions of years. This process qualifies coal as a fossil fuel.

4. **Conclusion**: Based on the analysis, the only option that qualifies as a fossil fuel is coal. Therefore, the correct answer to the question is coal.

**Final Answer**: An example of fossil fuel is coal.

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