Lithosphere is reservoir of

Options

A. Carbon
B. Oxygen
C. Phosphorus
D. Nitrogen

Explanation

### Step-by-Step Solution:

1. **Understanding the Layers of the Earth**:
- The Earth is composed of four main layers: lithosphere, hydrosphere, biosphere, and atmosphere.
- The lithosphere is the outermost layer of the Earth, which includes the crust and the uppermost mantle.

2. **Defining Lithosphere**:
- The lithosphere is characterized as the hard and rigid outer layer of the Earth. It is primarily made up of rocks and minerals.

3. **Identifying the Reservoirs**:
- Each layer of the Earth serves as a reservoir for different elements.
- The lithosphere specifically acts as a reservoir for certain nutrients and minerals.

4. **Determining the Correct Element**:
- Among the options provided (carbon, oxygen, phosphorus, nitrogen), we need to identify which element is stored in the lithosphere.
- The lithosphere is known to be a significant reservoir of phosphorus, which is essential for plant growth and is a key nutrient in ecosystems.

5. **Conclusion**:
- Therefore, the correct answer to the question "Lithosphere is a reservoir of?" is phosphorus.