Red algae is red due to the presence of :-

Options

A. R-Phycocyanin
B. R-Phycoerythrin
C. C-Phycocyanin
D. C-Phycoerythrin

Answer

**Step-by-Step Solution:**

1. **Understanding Algal Classification**: Algae can be classified based on their pigments into three main categories: green algae, brown algae, and red algae. Each type contains chlorophyll but also has accessory pigments that contribute to their color.

2. **Identifying Pigments in Red Algae**: Red algae contain chlorophyll A and chlorophyll D, along with specific accessory pigments. The key accessory pigment that gives red algae its characteristic color is phycoerythrin.

3. **Role of Phycoerythrin**: Phycoerythrin is a pigment that absorbs light in the blue and green wavelengths, reflecting red light, which is why red algae appear red. The specific form of phycoerythrin present in red algae is R-phycoerythrin.

4. **Conclusion**: Given the presence of R-phycoerythrin, it can be concluded that red algae are red due to this pigment.

5. **Final Answer**: The correct answer is R-phycoerythrin.

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