Pure water can be obtained from sea water by

Options

A. Centrifugation
B. Plasmolysis
C. Reverse osmosis
D. Sedimentation

Answer

To solve the question "Pure water can be obtained from sea water by", we will analyze the options provided and determine the correct method for obtaining pure water from seawater.

### Step-by-Step Solution:

1. **Understanding the Composition of Seawater**:
- Seawater contains a high concentration of salts and other impurities. To obtain pure water, we need to remove these salts.

2. **Identifying the Process of Desalination**:
- The process of removing salts from seawater is known as desalination. There are various methods for desalination, but we need to identify the most suitable one from the given options.

3. **Evaluating the Options**:
- **Centrifugation**: This method separates components based on density but is not effective for desalination.
- **Plasma Lysis**: This is a biological process and is not relevant to desalination of seawater.
- **Reverse Osmosis**: This is a well-known method for desalination where pressure is applied to seawater, forcing water through a semi-permeable membrane, leaving salts behind.
- **Sedimentation**: This process is used to settle out solids from liquids but does not remove dissolved salts.

4. **Conclusion**:
- The most effective method for obtaining pure water from seawater among the options provided is **Reverse Osmosis**.

### Final Answer:
Pure water can be obtained from seawater by **Reverse Osmosis**.

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