Which one of the following is a renewable source of energy?

Options

A. Petroleum
B. Coal
C. Nuclear fuel
D. Trees

Answer

To determine which of the given options is a renewable source of energy, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Renewable Energy**:
- Renewable energy sources are those that can be replenished naturally over time. They are sustainable and can be used repeatedly without depleting the resource.

2. **Identify the Given Options**:
- The options provided are:
- A) Petroleum
- B) Coal
- C) Nuclear Fuel
- D) Trees

3. **Analyze Each Option**:
- **Petroleum**: This is a fossil fuel formed from the remains of ancient marine organisms. It takes millions of years to form and cannot be replenished in a human time scale, making it a non-renewable resource.
- **Coal**: Similar to petroleum, coal is also a fossil fuel formed from the remains of plants and animals over millions of years. It is non-renewable as it cannot be replenished quickly.
- **Nuclear Fuel**: This typically refers to uranium or thorium, which are mined from the earth and take millions of years to form. Once used, they cannot be replaced quickly, making them non-renewable.
- **Trees**: Trees are a natural resource that can be replenished through planting and sustainable forestry practices. They grow back over time, making them a renewable resource.

4. **Conclude the Correct Answer**:
- Based on the analysis, the only option that qualifies as a renewable source of energy is **D) Trees**.

### Final Answer:
The correct answer is **D) Trees**.

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