Chlorofluorocarbon (CFC) is mainly responsible for:

Options

A. Reduction in ozone
B. Ozone formation
C. Formation of leghaemoglobin
D. Enhance chlorophyll formation

Answer

### Step-by-Step Solution:

1. **Understanding CFCs**: Chlorofluorocarbons (CFCs) are chemical compounds that were commonly used in various applications such as aerosol sprays, refrigerants, and foam-blowing agents.

2. **CFCs and Ozone Layer**: CFCs are known to have a significant impact on the ozone layer. When released into the atmosphere, they eventually reach the stratosphere where they undergo photodissociation, releasing chlorine atoms.

3. **Ozone Formation and Degradation**: Ozone (O3) is formed from oxygen (O2) through a process that involves ultraviolet (UV) light. The balance between the formation and degradation of ozone is crucial for maintaining the ozone layer.

4. **Role of Chlorine**: The chlorine atoms released from CFCs act as catalysts in the degradation of ozone. This means that they can break down ozone molecules (O3) into oxygen molecules (O2), thus reducing the overall concentration of ozone in the stratosphere.

5. **Consequences of Ozone Depletion**: The depletion of the ozone layer leads to the formation of an "ozone hole," particularly observed over the Antarctic region. This allows harmful UV radiation to penetrate the atmosphere, which can lead to various health issues such as skin cancer, cataracts, and other mutations.

6. **Conclusion**: Therefore, the main responsibility of CFCs is the depletion of the ozone layer, making option number 1 the correct answer.

### Final Answer:
Chlorofluorocarbon (CFC) is mainly responsible for the depletion of the ozone layer.

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