The electromagnetic waves used in the telecommunication are

Options

A. ultraviolet
B. infra-red
C. visible
D. microwaves

Answer

To solve the question about the electromagnetic waves used in telecommunications, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Telecommunication**:
- Telecommunication refers to the exchange of information over distances using electronic means. This includes devices like radios, televisions, and satellites.

2. **Identify the Types of Electromagnetic Waves**:
- Electromagnetic waves are classified into various types based on their frequency and wavelength. These include radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

3. **Determine the Relevant Electromagnetic Waves for Telecommunication**:
- In telecommunication, different frequencies of electromagnetic waves are utilized. The most commonly used waves for communication purposes are microwaves and radio waves.

4. **Focus on the Specific Range of Microwaves**:
- Microwaves are particularly important in telecommunications. The frequency range for microwaves used in telecommunications typically spans from 1 GHz to 300 GHz.

5. **Select the Correct Answer**:
- Based on the information gathered, the correct answer to the question is that the electromagnetic waves used in telecommunications are **microwaves**.

### Final Answer:
The electromagnetic waves used in telecommunications are microwaves.

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