Name the optical phenomenon due to which the sky appears blue.

Explanation

**Step-by-Step Solution:**

1. **Identify the Optical Phenomenon**: The optical phenomenon responsible for the blue appearance of the sky is known as "scattering of light."

2. **Understanding Scattering**: Scattering occurs when light rays interact with particles in the atmosphere. Different wavelengths (or colors) of light scatter differently when they encounter these particles.

3. **Color Scattering**: Among the various colors of light, blue light has a shorter wavelength compared to other colors. This shorter wavelength allows it to scatter more effectively when it interacts with the molecules in the atmosphere.

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