Brown algae is characterised by the presence of

Options

A. Fucoxanthin
B. Haemastochrome
C. Phycocyanin
D. Phycoerythrin

Answer

**Step-by-Step Solution:**

1. **Understanding Brown Algae**: Brown algae belong to the group of algae known as Phaeophyceae. They are primarily found in marine environments and are characterized by their brown color.

2. **Identifying Key Pigments**: The color of brown algae is primarily due to the presence of specific pigments. The question asks which pigment is characteristic of brown algae.

3. **Evaluating the Options**:
- **Phycoxanthin**: This is a pigment that gives brown algae their distinctive color and is a characteristic feature of these organisms.
- **Hematochrome**: This pigment is not found in any type of algae, making it an incorrect option.
- **Phycocyanin**: This pigment is associated with blue-green algae (cyanobacteria), not brown algae.
- **Phycoerythrin**: This pigment is found in red algae, thus it is also not a characteristic of brown algae.

4. **Conclusion**: Based on the evaluation of the pigments, the only pigment that is characteristic of brown algae is phycoxanthin.

**Final Answer**: Brown algae is characterized by the presence of phycoxanthin.

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