The major pollutant for ozone depletion is:

Options

A. `CO`
B. `CO_2`
C. `NO_2`
D. `CFC`

Answer

**Step-by-Step Solution:**

1. **Understanding Ozone Depletion**: Ozone depletion refers to the thinning of the ozone layer in the Earth's stratosphere, which protects us from harmful ultraviolet (UV) radiation from the sun.

2. **Identifying Major Pollutants**: Various substances can contribute to ozone depletion, but we need to identify the major pollutant among the given options.

3. **Recognizing CFCs**: The major pollutant responsible for ozone depletion is Chlorofluorocarbons (CFCs). These are man-made compounds that were commonly used in air conditioning, refrigeration, and aerosol propellants.

4. **Behavior of CFCs in the Atmosphere**: CFCs are stable and non-reactive in the lower atmosphere, which allows them to persist for a long time. However, when they reach the stratosphere, they are broken down by UV radiation, releasing chlorine atoms.

5. **Chlorine's Role in Ozone Depletion**: The chlorine atoms released from CFCs react with ozone (O3) molecules, leading to the depletion of the ozone layer. This reaction can destroy thousands of ozone molecules for each chlorine atom.

6. **Conclusion**: Therefore, the major pollutant for ozone depletion is CFCs, making option no. 4 the correct answer.

**Final Answer**: The major pollutant for ozone depletion is CFCs (Chlorofluorocarbons).

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