Which of the following is used as fire extinguisher under the name pyrene ?

Options

A. `CO_(2)`
B. `C Cl_(4)`
C. `CH_(2) =CH -CI`
D. `CI-CH= CH- CI`

Answer

To solve the question "Which of the following is used as a fire extinguisher under the name pyrene?", we will analyze the options provided.

### Step-by-Step Solution:

1. **Identify the Options**: The question provides multiple options, but we will focus on identifying which one is associated with the trade name "Pyrene".

2. **Evaluate Each Option**:
- **Option 1: Carbon Dioxide (CO2)**:
- Carbon dioxide is indeed used as a fire extinguisher. However, it is not known by the name "Pyrene". Therefore, this option is incorrect.

- **Option 2: Carbon Tetrachloride (CCl4)**:
- Carbon tetrachloride is also used as a fire extinguisher. Importantly, it is known under the trade name "Pyrene". This makes this option a strong candidate for the correct answer.

- **Option 3 and 4**:
- Without specific names provided, we can assume they are other chemicals that do not commonly serve as fire extinguishers or are not known by the name "Pyrene". Thus, they are likely incorrect.

3. **Conclusion**:
- After evaluating the options, we find that the correct answer is **Option 2: Carbon Tetrachloride (CCl4)**, as it is used as a fire extinguisher under the trade name "Pyrene".

### Final Answer:
The correct answer is **Carbon Tetrachloride (CCl4)**, which is used as a fire extinguisher under the name "Pyrene".

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