Earth is protected from UV rays by

Options

A. `N_(2)`
B. `O_(2)`
C. `O_(3)`
D. `SO_(3)`

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks how the Earth is protected from UV rays. UV rays are harmful radiations emitted by the Sun.

2. **Identifying the Protective Layer**: The Earth has a natural layer in the upper atmosphere that plays a crucial role in filtering out harmful UV radiation. This layer is primarily composed of ozone (O3).

3. **Role of Ozone Layer**: The ozone layer absorbs a significant portion of the Sun's harmful UV radiation, preventing it from reaching the Earth's surface. This protection is vital for the health of all living organisms, including humans.

4. **Formation of Ozone**: Ozone is formed in the atmosphere when UV rays interact with oxygen (O2). Specifically, UV radiation causes the dissociation of O2 molecules into individual oxygen atoms. These oxygen atoms can then react with other O2 molecules to form ozone (O3).

5. **Conclusion**: Therefore, the Earth is protected from harmful UV rays primarily by the ozone layer, which is made up of ozone gas (O3).

**Final Answer**: Earth is protected from UV rays by the ozone layer (O3).

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