The space waves which are affected seriously by atmospheric conditions are

Options

A. MF
B. HF
C. VHF
D. UHF

Answer

To answer the question about which space waves are seriously affected by atmospheric conditions, we can analyze the types of waves used in communication systems.

### Step-by-Step Solution:

1. **Understanding Space Waves**: Space waves are electromagnetic waves that travel through the atmosphere and are used in various communication systems. They can be categorized into different types based on their frequency and propagation characteristics.

2. **Types of Space Waves**:
- **Microwaves**: These waves have frequencies ranging from 1 GHz to 300 GHz. They are used in line-of-sight communication and can be affected by atmospheric conditions such as rain, fog, and humidity.
- **Radio Waves**: These waves have lower frequencies (below 1 GHz) and can diffract around obstacles. They are less affected by atmospheric conditions compared to microwaves.
- **Infrared Waves**: These waves are also used in communication but are not typically classified as space waves in the same context as microwaves and radio waves.

3. **Impact of Atmospheric Conditions**: Among these types, microwaves are particularly sensitive to atmospheric conditions. Factors such as rain, snow, and atmospheric attenuation can significantly affect microwave transmission.

4. **Conclusion**: Therefore, the space waves that are seriously affected by atmospheric conditions are **Microwaves**.

### Final Answer:
The space waves which are affected seriously by atmospheric conditions are **Microwaves**.

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