The zone which extends above troposphere up to 50 km above sea level and contains dinitrogen, dioxygen , ozone and little water vapour is called

Options

A. exosphere
B. mesosphere
C. ionosphere
D. stratosphere.

Answer

To solve the question regarding the zone that extends above the troposphere up to 50 km above sea level and contains dinitrogen, dioxygen, ozone, and little water vapor, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Layers of the Atmosphere**:
- The Earth's atmosphere is divided into several layers based on altitude. The primary layers are:
- Troposphere (up to 12 km)
- Stratosphere (12 km to 50 km)
- Mesosphere (50 km to 90 km)
- Thermosphere (90 km to 800 km)
- Exosphere (800 km to 3000 km)

2. **Identify the Relevant Layer**:
- The question specifies a zone that extends above the troposphere and up to 50 km.
- Since the troposphere extends up to 12 km, the next layer, which begins at 12 km and goes up to 50 km, is the stratosphere.

3. **Components of the Stratosphere**:
- The stratosphere contains various gases, including:
- Dinitrogen (N₂)
- Dioxygen (O₂)
- Ozone (O₃)
- A small amount of water vapor
- This matches the description given in the question.

4. **Conclusion**:
- Based on the information about the layers and their components, the zone that extends above the troposphere up to 50 km and contains the specified gases is called the **Stratosphere**.

### Final Answer:
The zone which extends above the troposphere up to 50 km above sea level and contains dinitrogen, dioxygen, ozone, and little water vapor is called the **Stratosphere**.

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