Which of the following is used in the application of radio transmission ?

Options

A. X-rays
B. Radio waves
C. UV rays
D. None

Explanation

To solve the question "Which of the following is used in the application of radio transmission?" we will analyze the given options step by step.

### Step 1: Identify the Options
The options provided are:
1. X-rays
2. Radio waves
3. Ultraviolet rays
4. None of the above

### Step 2: Understand the Nature of Each Option
- **X-rays**: These are high-energy electromagnetic waves primarily used in medical imaging and not suitable for radio transmission.
- **Radio waves**: These are low-frequency electromagnetic waves that can travel long distances and are specifically designed for communication, including radio transmission.
- **Ultraviolet rays**: These are higher frequency waves than visible light and are used in applications like sterilization and fluorescence but are not used for radio transmission.
- **None of the above**: This option indicates that none of the previous options are correct, which we will evaluate after analyzing the others.

### Step 3: Determine the Correct Option
Given that radio waves are specifically designed for communication and can travel long distances effectively, they are the most suitable option for radio transmission.

### Conclusion
The correct answer to the question is **Radio waves**.

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