Ozone is absent in

Options

A. Troposphere
B. Mesosphere
C. Stratosphere
D. None of the above.

Answer

**Step-by-Step Solution:**

1. **Understanding the Layers of the Atmosphere**: The Earth's atmosphere is divided into several layers, including the troposphere, stratosphere, mesosphere, and thermosphere. Each layer has distinct characteristics and functions.

2. **Identifying Ozone Presence**: Ozone (O3) is primarily found in the stratosphere, where it forms the ozone layer that protects the Earth from harmful ultraviolet (UV) radiation.

3. **Analyzing Each Layer**:
- **Troposphere**: This is the lowest layer of the atmosphere, where weather occurs, and it contains some ozone, although not in significant amounts.
- **Stratosphere**: This layer is located above the troposphere and contains the majority of the Earth's ozone.
- **Mesosphere**: This layer is located above the stratosphere and is characterized by a decrease in temperature with altitude. It is known that ozone is absent in this layer.
- **Thermosphere**: This is the layer above the mesosphere, where temperatures can rise significantly, but it is not relevant to the question about ozone absence.

4. **Conclusion**: Based on the analysis, the layer where ozone is absent is the mesosphere.

5. **Final Answer**: The correct answer is **mesosphere**.

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