The main reserve food material of class Chlorophyceae is :

Options

A. fat
B. starch
C. glycogen
D. volutin

Explanation

To answer the question about the main reserve food material of class Chlorophyceae, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Class**: The question refers to the class Chlorophyceae, which is commonly known as green algae.

2. **Understand the Characteristics of Chlorophyceae**: Members of this class are primarily aquatic and can be unicellular or multicellular. They contain chlorophyll, which gives them their green color.

3. **Examine the Reserve Food Material**: In green algae, the reserve food material is stored in specialized structures known as pyrenoids.

4. **Determine the Type of Reserve Food Material**: The main reserve food material stored in the pyrenoids of green algae is starch.

5. **Evaluate the Options**:
- **Fat**: This is primarily a reserve food material in animals, not in green algae.
- **Starch**: This is the correct answer as it is the reserve food material in green algae.
- **Glycogen**: This is also a reserve food material but is found in animals, not in green algae.
- **Volatile**: This term does not refer to a reserve food material in green algae or any other group mentioned.

6. **Conclude the Answer**: Based on the information, the main reserve food material of class Chlorophyceae is starch.

### Final Answer:
The main reserve food material of class Chlorophyceae is **starch**.

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