Which of the following is an exhaustible natural resource?

Options

A. Oxygen
B. Air
C. Sunlight
D. Forests

Explanation

To determine which of the given options is an exhaustible natural resource, we can follow these steps:

### Step 1: Understand the Definition of Exhaustible Natural Resources
Exhaustible natural resources are those that are available in limited quantities and can be completely depleted through human activities. Examples include fossil fuels, minerals, and forests.

### Step 2: Analyze Each Option
1. **Oxygen**: This is a vital gas that is continuously produced by plants through photosynthesis and is not limited in quantity.
2. **Air**: Similar to oxygen, air is a mixture of gases that is abundant and not exhaustible.
3. **Sunlight**: Sunlight is a renewable resource that is available in abundance and cannot be exhausted.
4. **Forest**: Forests are natural resources that can be depleted through deforestation and over-exploitation.

### Step 3: Identify the Exhaustible Resource
From the analysis:
- **Oxygen**, **air**, and **sunlight** are not exhaustible.
- **Forest** is an exhaustible natural resource because it can be depleted if not managed sustainably.

### Conclusion
The correct answer is **forest**, as it is the only exhaustible natural resource among the options provided.

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