Ozone layer of upper atmosphere is being destroyed by:

Options

A. Chlorofluorocarbon
B. `SO_(2)`
C. photochemical oxidants/`O_(2)` and `CO_(2)`
D. smog.

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks about the destruction of the ozone layer in the upper atmosphere. It is important to identify the substances responsible for this depletion.

2. **Define the Ozone Layer**: The ozone layer is a region of Earth's stratosphere that contains a high concentration of ozone (O3). It plays a crucial role in protecting the Earth from harmful ultraviolet (UV) radiation from the sun.

3. **Identify Potential Options**: The question likely provides multiple-choice options. In this case, we focus on identifying which of these options is known to deplete the ozone layer.

4. **Recognize the Role of Chlorofluorocarbons (CFCs)**: CFCs are chemical compounds that have been widely used in refrigeration, air conditioning, and aerosol propellants. They are known to be harmful to the ozone layer.

5. **Mechanism of Ozone Depletion**: When CFCs are released into the atmosphere, they eventually reach the stratosphere. Here, they are broken down by UV radiation, releasing chlorine atoms. These chlorine atoms react with ozone (O3), converting it into oxygen (O2) and thereby depleting the ozone layer.

6. **Conclusion**: Based on the information gathered, the correct answer to the question is that the ozone layer of the upper atmosphere is being destroyed by chlorofluorocarbons (CFCs).

7. **Final Answer**: Therefore, the answer is **Option A: Chlorofluorocarbon**.

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