Ozone is not present in

Options

A. thermosphere
B. Mesosphere
C. Stratosphere
D. `O_(3)` layer

Answer

To solve the question "Ozone is not present in," we will analyze the different layers of the Earth's atmosphere and identify where ozone is found and where it is not.

### Step-by-Step Solution:

1. **Identify the Layers of the Atmosphere**:
- The Earth's atmosphere is divided into several layers:
- Troposphere
- Stratosphere
- Mesosphere
- Thermosphere
- Exosphere

2. **Locate the Ozone Layer**:
- Ozone (O₃) is primarily found in the Stratosphere, which is the second layer of the atmosphere, above the Troposphere.
- The ozone layer is crucial for absorbing the majority of the sun's harmful ultraviolet radiation.

3. **Determine Where Ozone is Absent**:
- In the Troposphere, ozone is present but mainly as a pollutant and not in the form of the protective ozone layer.
- In the Mesosphere, there is very little ozone present.
- In the Thermosphere, ozone is not present at all.
- The Exosphere is the outermost layer, where ozone is also not present.

4. **Conclusion**:
- Based on the analysis, the layers where ozone is not present include the Thermosphere and the Exosphere. However, the Thermosphere is specifically noted for the absence of ozone.

Thus, the correct answer to the question "Ozone is not present in" is the **Thermosphere**.