Most effective wavelength of light for photosynthesis is

Options

A. Green
B. UV light
C. Red
D. Yellow

Answer

### Step-by-Step Solution:

1. **Understanding Photosynthesis**: Photosynthesis is the process by which plants convert light energy into chemical energy, primarily using sunlight.

2. **Identifying Light Wavelengths**: Light can be categorized into different wavelengths, including ultraviolet (UV), visible light, and infrared (IR). The visible light spectrum ranges from approximately 400 to 700 nanometers.

3. **Visible Light Spectrum**: The visible light spectrum includes various colors: violet, blue, green, yellow, orange, and red. Each color has a specific wavelength, with red light having the longest wavelength in the visible spectrum.

4. **Role of Different Wavelengths**:
- **Green Light**: Plants reflect green light, which is why they appear green. This wavelength is not effectively used in photosynthesis.
- **UV Light**: UV light is mostly absorbed by the ozone layer and is not significantly utilized in photosynthesis.
- **Red Light**: Red light (around 620-750 nm) is highly effective for photosynthesis. It is absorbed by chlorophyll, the pigment responsible for capturing light energy.

5. **Conclusion**: Based on the information about light absorption and the effectiveness of different wavelengths in photosynthesis, the most effective wavelength of light for photosynthesis is red light.

### Final Answer:
The most effective wavelength of light for photosynthesis is **red light**.

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