Which of the following have lowest frequency ?

Options

A. Radio waves
B. Infra-red
C. Ultraviolet
D. Gamma rays

Explanation

To determine which of the following electromagnetic waves has the lowest frequency, we can analyze the given options: radio waves, infrared, ultraviolet, and gamma rays.

### Step-by-Step Solution:

1. **Understanding the Electromagnetic Spectrum**:
The electromagnetic spectrum is a range of all the different frequencies of electromagnetic radiation. It includes various types of waves, which are arranged from the highest frequency to the lowest frequency.

2. **List the Types of Waves in Order of Frequency**:
- Cosmic Rays (highest frequency)
- Gamma Rays
- X-rays
- Ultraviolet Rays
- Visible Light
- Infrared Rays
- Microwaves
- Radio Waves (lowest frequency)

3. **Identify the Frequencies of the Given Options**:
- **Radio Waves**: Lowest frequency
- **Infrared**: Higher frequency than radio waves
- **Ultraviolet**: Higher frequency than infrared
- **Gamma Rays**: Highest frequency among the options

4. **Conclusion**:
From the analysis, it is clear that out of the given options, **radio waves** have the lowest frequency.

### Final Answer:
The option with the lowest frequency is **radio waves**.

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