Mannitol is the stored food in :-

Options

A. Porphyra
B. Fucus
C. Gracillaria
D. Chara

Answer

To solve the question "Mannitol is the stored food in:", we need to analyze the options provided and understand the characteristics of each organism listed.

### Step-by-Step Solution:

1. **Identify the Organisms**: The options given are:
- A. Polyphyra
- B. Fucus
- C. Gracilaria
- D. Chara

2. **Classify the Organisms**:
- **Fucus**: This organism belongs to the class Phaeophyceae (brown algae).
- **Gracilaria**: This belongs to the class Rhodophyceae (red algae).
- **Chara**: This belongs to the class Chlorophyceae (green algae).
- **Polyphyra**: This is also classified under Rhodophyceae.

3. **Stored Food Analysis**:
- **Fucus**: The stored food in Fucus is mannitol, which is a type of sugar alcohol.
- **Gracilaria and Polyphyra**: These organisms store food in the form of Floridian starch.
- **Chara**: The stored food in Chara is starch and oil.

4. **Conclusion**: Based on the classification and the type of stored food, we can conclude that mannitol is specifically stored in Fucus.

### Final Answer:
The answer is **B. Fucus**.

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