Rhodophyta are commonly called red algae because of the predominance of the

Options

A. red pigment,r-phycoerythrin in their body
B. red pigment,c-phycoerythrin in their body
C. red pigment,r-phycocyanin in their body
D. red pigment,c-phycocyanin in their body

Answer

**Step-by-Step Solution:**

1. **Understanding Algae**: Begin by defining what algae are. Algae are a diverse group of eukaryotic organisms that are primarily photosynthetic and mostly aquatic.

2. **Types of Algae**: Recognize that there are three main types of algae:
- **Brown Algae** (Phaeophyceae)
- **Green Algae** (Chlorophyceae)
- **Red Algae** (Rhodophyceae)

3. **Identifying Rhodophyta**: Focus on Rhodophyta, commonly known as red algae. This group is characterized by its distinct color.

4. **Pigments in Rhodophyta**: Understand that the red color in Rhodophyta is due to the predominance of specific pigments. The main pigment responsible for the red coloration is **R-phycoerythrin**.

5. **Other Pigments**: Note that in addition to R-phycoerythrin, red algae also contain other pigments, such as pigment A and pigment D, but these do not contribute to the red coloration.

6. **Conclusion**: Conclude that the correct answer to the question is that Rhodophyta are commonly called red algae because of the predominance of **R-phycoerythrin**.

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