Fossil fuels are obtained from:

Options

A. remains of non-living materials.
B. dead remains of insects only.
C. dead remains of birds only.
D. dead remains of living organisms.

Answer

**Step-by-Step Solution:**

1. **Understanding Fossil Fuels**: Fossil fuels are natural resources that are primarily composed of carbon and are derived from the remains of ancient living organisms.

2. **Source of Fossil Fuels**: The primary source of fossil fuels is the dead remains of living organisms. These organisms include plants and animals that lived millions of years ago.

3. **Process of Formation**: When these dead remains are buried under layers of earth, they undergo a transformation process. Over thousands of years, due to high temperature and pressure, these remains are converted into fossil fuels.

4. **Types of Fossil Fuels**: The main types of fossil fuels include coal, petroleum (oil), and natural gas. Each of these fuels has a high carbon content and is used for various energy needs.

5. **Conclusion**: Therefore, fossil fuels are obtained from the dead remains of living organisms that have been subjected to geological processes over a long period.

**Final Answer**: Fossil fuels are obtained from the dead remains of living organisms.

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