What protects the earth from UV radiations ?

Options

A. A layer of oxygen gas
B. A layer of ozone gas
C. A layer of nitrogen oxide
D. layer of `SO_(2)`

Answer

**Step-by-Step Solution:**

1. **Understanding UV Radiation**: Ultraviolet (UV) radiation is a type of energy emitted by the sun. While it is essential for certain processes, excessive exposure can be harmful to living organisms and the environment.

2. **Identifying Protective Layers**: The Earth has various layers in its atmosphere that serve different functions. Among these layers, some are responsible for filtering harmful radiation.

3. **Evaluating Options**: The question provides four options regarding what protects the Earth from UV radiation:
- Option 1: A layer of oxygen gas
- Option 2: A layer of ozone gas
- Option 3: A layer of nitrogen oxide
- Option 4: A layer of sulfur dioxide

4. **Focusing on Ozone Layer**: The ozone layer, which is primarily composed of ozone (O3) molecules, is located in the stratosphere. This layer plays a crucial role in absorbing the majority of the sun's harmful UV radiation.

5. **Conclusion**: Given the importance of the ozone layer in protecting the Earth from UV radiation, the correct answer is **Option 2: A layer of ozone gas**.

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