The zone of atmosphere in which the ozone layer is present is called: (A) Troposphere (B) Ionosphere (C) Mesosphere (D) Stratosphere

Options

A. Troposphere
B. Ionosphere
C. Mesosphere
D. Stratosphere

Answer

To solve the question regarding the zone of the atmosphere in which the ozone layer is present, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Layers of the Atmosphere**:
- The atmosphere is divided into several layers: Troposphere, Stratosphere, Mesosphere, Thermosphere, and Ionosphere.

2. **Understand the Function of Each Layer**:
- **Troposphere**: This is the layer where we live and where weather occurs. It does not contain the ozone layer.
- **Stratosphere**: This layer is located above the troposphere and is where the ozone layer is found. The ozone in this layer absorbs harmful ultraviolet (UV) radiation from the sun.
- **Mesosphere**: This layer is above the stratosphere and does not contain the ozone layer.
- **Thermosphere**: This is the uppermost layer of the atmosphere, above the mesosphere, and also does not contain the ozone layer.
- **Ionosphere**: This is not a distinct layer but refers to the part of the atmosphere that is ionized by solar and cosmic radiation, and it is located within the thermosphere.

3. **Evaluate the Options**:
- (A) Troposphere: Incorrect, as the ozone layer is not present here.
- (B) Ionosphere: Incorrect, as this is not a distinct layer containing the ozone layer.
- (C) Mesosphere: Incorrect, as the ozone layer is not present in this layer.
- (D) Stratosphere: Correct, as the ozone layer is located in this layer.

4. **Conclusion**:
- Based on the above analysis, the correct answer is (D) Stratosphere.

### Final Answer:
(D) Stratosphere