Which of the following device can control air pollution ?

Options

A. Scrubbers
B. Effluent treatment
C. Electrostatic precipitator
D. Both (1) & (3)

Answer

To solve the question "Which of the following devices can control air pollution?", we will analyze each option provided.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- Option 1: Scrubbers
- Option 2: Effluent Treatment
- Option 3: Electrostatic Precipitator
- Option 4: Both 1 and 3

2. **Evaluate Option 1 - Scrubbers**:
- Scrubbers are devices that use liquid to remove particulate matter or gases from industrial exhaust.
- They are specifically designed to control air pollution by filtering out harmful substances from the air.
- **Conclusion**: This option is correct.

3. **Evaluate Option 2 - Effluent Treatment**:
- Effluent treatment refers to the process of treating wastewater or sewage to make it safe for disposal or reuse.
- This process is primarily focused on water pollution rather than air pollution.
- **Conclusion**: This option is incorrect.

4. **Evaluate Option 3 - Electrostatic Precipitator**:
- An electrostatic precipitator is a filterless device that controls air pollution by removing dust and smoke particles from flowing gases in the air.
- It is effective in reducing airborne pollutants.
- **Conclusion**: This option is correct.

5. **Evaluate Option 4 - Both 1 and 3**:
- Since both scrubbers (Option 1) and electrostatic precipitators (Option 3) are devices that can control air pollution, this option is valid.
- **Conclusion**: This option is correct.

6. **Final Answer**: The correct answer is **Option 4: Both 1 and 3**.