The device normally used to remove gaseous pollutants from polluted air but can remove large particulate matter as well, is

Options

A. electrostatic precipitator
B. cyclonic separator
C. trajectory separator
D. scrubber

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for a device that removes both gaseous pollutants and large particulate matter from polluted air.

2. **Evaluate the Options**: The options provided are:
- Electrostatic precipitators
- Cyclonic separator
- Trajectory separator
- Scrubber

3. **Analyze Each Option**:
- **Electrostatic Precipitators**: These devices primarily remove particulate matter from gases using electrical energy. They are effective for small particles but do not effectively remove large particulate matter or gaseous pollutants.
- **Cyclonic Separator**: This device is designed to separate particles from a gas stream using centrifugal force. It is more suited for larger particles and does not effectively remove gaseous pollutants.
- **Trajectory Separator**: Similar to the cyclonic separator, this device is used to separate particles based on their trajectory in a gas stream. It is not effective for removing gaseous pollutants.
- **Scrubber**: Scrubbers are designed to remove both gaseous pollutants and larger particulate matter from the air. They work by passing the polluted air through a liquid that absorbs the gases and captures larger particles.

4. **Identify the Correct Answer**: Based on the analysis, the scrubber is the only device that effectively removes both gaseous pollutants and larger particulate matter from polluted air.

5. **Conclusion**: The correct answer to the question is **Scrubber**.

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