Classification of algae is mainly based on :-

Options

A. Reproductive organs
B. Structure of spores
C. Pigments
D. Stored food

Answer

**Step-by-Step Solution:**

1. **Understanding Algae**: Algae are simple, chlorophyll-bearing, thalloid plants that can perform photosynthesis. They are an important group of organisms in the plant kingdom.

2. **Classification Criteria**: Algae are classified into different groups based on various characteristics. The main criteria for classification include:
- Reproductive organs
- Structure of spores
- Pigments
- Stored food

3. **Identifying the Main Basis for Classification**: Among the options provided, the most significant factor for the classification of algae is their pigments. Different types of algae have distinct pigments that give them their characteristic colors.

4. **Types of Algae and Their Pigments**:
- **Chlorophyceae (Green Algae)**: Characterized by pigments such as chlorophyll A, chlorophyll B, carotenes, and xanthophyll.
- **Phaeophyceae (Brown Algae)**: Contains the pigment fucoxanthin, which gives them a brown color.
- **Rhodophyceae (Red Algae)**: Characterized by pigments like phycoerythrin and phycocyanin, which give them a red color.

5. **Conclusion**: Based on the information above, the classification of algae is mainly based on their pigments. Therefore, the correct answer is "pigments".

**Final Answer**: The classification of algae is mainly based on pigments.

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