In fire extinguishers , following is used

Options

A. `CHCl_3`
B. `CS_2`
C. `"CCl"_4`
D. `CH_2Cl_2`

Explanation

### Step-by-Step Solution:

1. **Understanding the Function of Fire Extinguishers**:
Fire extinguishers are devices used to put out fires by removing one of the essential elements needed for combustion. The three elements required for combustion are heat, fuel, and oxygen (often referred to as the fire triangle).

2. **Identifying the Chemical Used**:
In this case, the question specifies the use of Carbon Tetrachloride (CCl4) in fire extinguishers. Carbon Tetrachloride is a chemical compound that is a colorless liquid at room temperature.

3. **Mechanism of Action**:
- When Carbon Tetrachloride is released from the fire extinguisher, it forms heavy vapors.
- These vapors are non-combustible, meaning they do not support combustion and do not burn themselves.
- The heavy vapors of CCl4 displace the oxygen in the vicinity of the fire.

4. **Cutting Off the Oxygen Supply**:
- Since fire requires oxygen to sustain combustion, the presence of Carbon Tetrachloride vapors effectively cuts off the oxygen supply to the fire.
- Without oxygen, the combustion process cannot continue, leading to the extinguishing of the fire.

5. **Conclusion**:
Therefore, Carbon Tetrachloride (CCl4) is used in fire extinguishers primarily because it is effective in displacing oxygen, thus putting out the fire by interrupting the combustion process.