What is the basis of classification of algae?

Explanation

**Step-by-Step Solution:**

1. **Definition of Algae**: Algae are photosynthetic aquatic organisms that can perform photosynthesis due to the presence of pigments.

2. **Presence of Pigments**: The classification of algae is primarily based on the types of pigments they contain. The main pigments involved are chlorophyll A, B, C, and D, as well as other accessory pigments.

3. **Main Categories of Algae**: Algae are classified into three main groups based on their pigment composition:
- **Green Algae**: These contain chlorophyll A and B, which gives them their green color. An example of green algae is *Chara*.
...