Desalination of sea water can be done by

Options

A. Filtration
B. Osmosis
C. Reverse osmosis
D. Diffusion

Answer

### Step-by-Step Solution:

1. **Understanding Desalination**:
- Desalination is the process of removing salt and other impurities from seawater to make it suitable for human consumption and irrigation.

2. **Identifying the Need for Desalination**:
- Seawater contains a high concentration of salts (brine), which makes it unsafe for drinking and other uses. Therefore, desalination is essential to convert seawater into fresh water.

3. **Exploring Methods of Desalination**:
- There are several methods for desalination, including distillation, electrodialysis, and reverse osmosis. Each method has its own advantages and disadvantages.

4. **Focusing on Reverse Osmosis**:
- Among the various methods, reverse osmosis is the most widely used and efficient technique for desalination. It involves forcing seawater through a semi-permeable membrane that allows water molecules to pass but blocks salt and other impurities.

5. **Conclusion**:
- Therefore, the correct answer to the question "Desalination of seawater can be done by" is reverse osmosis.

### Final Answer:
Desalination of seawater can be done by reverse osmosis.

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