Fuel formed under the earth's surface by the decomposition of organic matter is called :

Options

A. organic fuel
B. biogas
C. fossil fuel
D. underground fuel

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the fuel that is formed under the Earth's surface through the decomposition of organic matter.

2. **Identifying Organic Matter**: Organic matter refers to the remains of plants and animals that have died and decomposed over time.

3. **Decomposition Process**: This organic matter undergoes a long process of decomposition, primarily facilitated by microorganisms. This process can take thousands to millions of years.

4. **Formation of Fossil Fuels**: During this decomposition process, the remains of these plants and animals transform into fossil fuels. This transformation occurs deep within the Earth's crust.

5. **Examples of Fossil Fuels**: Common examples of fossil fuels include coal, petroleum (oil), and natural gas. These fuels are derived from the ancient organic matter that has been subjected to heat and pressure over geological time.

6. **Conclusion**: Based on the information above, the fuel formed under the Earth's surface by the decomposition of organic matter is called **fossil fuel**.

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