Ozone layer exists at oan altitude of

Options

A. 10-20 kms
B. 20-30 kms
C. 30-40 kms
D. 40-50 kms

Answer

To solve the question regarding the altitude at which the ozone layer exists, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the altitude at which the ozone layer exists. We have four options to choose from:
- Option 1: 10-20 km
- Option 2: 20-30 km
- Option 3: 30-40 km
- Option 4: 40-50 km

2. **Recall Information about the Ozone Layer**: The ozone layer is a region of Earth's stratosphere that absorbs most of the Sun's harmful ultraviolet (UV) radiation.

3. **Identify the Typical Altitude of the Ozone Layer**: Based on scientific knowledge, the ozone layer is generally found at an altitude of approximately 15 to 50 kilometers above the Earth's surface, with the highest concentration typically occurring between 20 to 30 kilometers.

4. **Narrow Down the Options**:
- Option 1 (10-20 km) is too low for the ozone layer.
- Option 2 (20-30 km) is within the range but not the highest concentration.
- Option 3 (30-40 km) is also within the range but still not the highest concentration.
- Option 4 (40-50 km) is at the upper limit of the ozone layer.

5. **Select the Correct Option**: The ozone layer is most commonly recognized to exist at an altitude of 40 to 50 kilometers, which corresponds to Option 4.

6. **Conclusion**: Therefore, the correct answer is that the ozone layer exists at an altitude of 40 to 50 kilometers.

### Final Answer:
The ozone layer exists at an altitude of **40 to 50 km** (Option 4).

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