Which of the following statements is correct ?

Options

A. Ozone hole is a hole formed in stratosphere from which ozone oozes out.
B. Ozone hole is a hole formed in the troposphere from which ozone oozes out.
C. Ozone hole is thinning of ozone layer of stratosphere at some places.
D. Ozone hole means vanishing of ozone layer around the earht completely.

Explanation

To determine which statement is correct regarding the ozone layer and ozone depletion, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding the Ozone Layer**:
- The ozone layer is a region of Earth's stratosphere that contains a high concentration of ozone (O₃) molecules. It plays a crucial role in absorbing the majority of the sun's harmful ultraviolet (UV) radiation.

2. **Evaluating Each Statement**:
- **Statement 1**: "Ozone hole is a hole on a stratosphere from which ozone comes out."
- **Analysis**: This statement is incorrect. The ozone hole refers to a significant reduction in ozone concentration in the stratosphere, not a literal hole from which ozone escapes.

- **Statement 2**: "Ozone layer is present in the troposphere."
- **Analysis**: This statement is also incorrect. The ozone layer is primarily located in the stratosphere, not the troposphere. The troposphere is the lowest layer of Earth's atmosphere where weather occurs.

- **Statement 3**: "Ozone is the thinning of ozone."
- **Analysis**: This statement is correct. The term "ozone depletion" refers to the thinning of the ozone layer, which has been observed over certain regions, particularly over Antarctica.

- **Statement 4**: "Ozone hole means vanishing of ozone layer around the earth completely."
- **Analysis**: This statement is incorrect. The ozone hole does not mean that the ozone layer has vanished completely; it refers to a significant thinning of the ozone layer in specific areas.

3. **Conclusion**:
- After evaluating all the statements, the **correct statement** is **Statement 3**: "Ozone is the thinning of ozone."

### Final Answer:
The correct statement is: **"Ozone is the thinning of ozone."**

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