The 'catalytic converters' are fitted in

Options

A. Smoke stacks
B. Automobiles
C. Nuclear plants
D. Sewage treatment plant

Answer

**Step-by-Step Solution:**

1. **Understanding the Function of Catalytic Converters:**
- Catalytic converters are devices used to reduce harmful emissions from vehicles. They contain catalysts that facilitate chemical reactions to convert toxic gases into less harmful substances.

2. **Identifying the Location of Catalytic Converters:**
- The question asks where catalytic converters are fitted. The options provided are smog packs, automobiles, nuclear plants, and sewage treatment plants.

3. **Analyzing the Options:**
- **Smog Packs:** These are not a common term associated with catalytic converters.
- **Automobiles:** Catalytic converters are widely used in vehicles to reduce harmful emissions.
- **Nuclear Plants:** These do not use catalytic converters as they deal with nuclear reactions and waste management.
- **Sewage Treatment Plants:** While they may have various treatment processes, catalytic converters are not typically used here.

4. **Conclusion:**
- Based on the analysis, catalytic converters are specifically fitted in **automobiles** to reduce the emission of harmful gases such as carbon monoxide, unburnt hydrocarbons, and nitrogen oxides.

5. **Final Answer:**
- The correct answer is **automobiles** (Option 2).

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