............. is renewable source of energy.

Options

A. Coal
B. Oil
C. Diesel
D. Biodiesel

Answer

**Step-by-Step Solution:**

1. **Understanding Renewable Energy Sources**: Renewable energy sources are those that can be replenished naturally over time. They are not finite and can be used repeatedly without the risk of depletion.

2. **Examples of Renewable Energy Sources**: Common examples include:
- **Solar Energy**: Energy harnessed from the sun's rays. It is abundant and can be captured using solar panels.
- **Wind Energy**: Energy generated from wind using turbines. Wind is a natural phenomenon that is constantly occurring.
- **Geothermal Energy**: Energy derived from the heat stored beneath the Earth's surface. This heat is continuously replenished by the Earth’s internal processes.
- **Biofuels (like Biodiesel)**: Fuels derived from organic materials that can be replenished through agricultural processes.

3. **Identifying a Renewable Source**: From the examples provided, we can identify that solar energy, wind energy, geothermal energy, and biodiesel are all renewable sources of energy.

4. **Conclusion**: Therefore, the answer to the question "............. is a renewable source of energy" can be filled with any of the examples mentioned, such as "Solar energy" or "Biodiesel".

**Final Answer**: Solar energy is a renewable source of energy.

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