The composition of tear gas is 

Options

A. `ClC_2 H_4 SC_2 H_4Cl`
B. `C Cl_3NO_2`
C. `COCl_2`
D. `CF_2Cl_2`

Answer

### Step-by-Step Solution:

1. **Understanding Tear Gas**: Tear gas is a chemical compound used for crowd control and self-defense. It causes irritation to the eyes and respiratory system, leading to tears and discomfort.

2. **Identifying the Options**: The question likely provides multiple options for the composition of tear gas. We need to analyze these options to find the correct one.

3. **Recognizing Common Tear Gas Compounds**: Common tear gases include CS gas (2-chlorobenzalmalononitrile) and CN gas (chloroacetophenone). However, the question specifically asks for the composition, which can also refer to other compounds.

4. **Finding the Correct Answer**: According to the information provided, the correct composition of tear gas is identified as CCl3NO2. This compound is known as trichloro nitromethane.

5. **Conclusion**: Therefore, the correct answer to the question regarding the composition of tear gas is CCl3NO2.

### Final Answer:
The composition of tear gas is CCl3NO2 (trichloro nitromethane).

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