Electromagnetic radiation with maximum wavelengths is :

Options

A. a.ultraviolet
B. b.radio wave
C. c.X-ray
D. d.infrared

Explanation

To solve the question regarding which electromagnetic radiation has the maximum wavelength, we can follow these steps:

### Step 1: Understand the Electromagnetic Spectrum
The electromagnetic spectrum consists of various types of electromagnetic radiation arranged in order of increasing wavelength and decreasing frequency. The order is as follows:
1. Gamma rays
2. X-rays
3. Ultraviolet rays
4. Visible light
5. Infrared rays
6. Microwaves
7. Radio waves

### Step 2: Analyze Wavelength and Frequency Relationship
As we move from gamma rays to radio waves in the electromagnetic spectrum:
- The wavelength increases.
- The frequency decreases.
- The energy of the radiation also decreases.

### Step 3: Identify the Type of Radiation with Maximum Wavelength
From the order of the electromagnetic spectrum, we can see that radio waves have the longest wavelength compared to the other types of radiation listed.

### Step 4: Conclusion
Therefore, the electromagnetic radiation with the maximum wavelength is **radio waves**.

### Final Answer
The correct option is **radio waves**.

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