Which one of the following statements is wrong

Options

A. Agar-agar is obtained from Gelidium and Gracilaria
B. Chlorella and Spirulina are used as space food
C. Mannitol is stored food in Rhodophyceae
D. Algin and carrageen are products of algae

Explanation

To determine which statement is wrong among the provided options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Identify the Statements**: We have four statements to evaluate:
- A) Agar-Agar is obtained from Gelidium and Gracilaria.
- B) Chlorella and Spirulina are used as space food.
- C) Manitol is stored food in Rhodophyta.
- D) Algin and Carrageenan are products of algae.

2. **Evaluate Statement A**:
- Agar-Agar is indeed obtained from Gelidium and Gracilaria, which are types of red algae.
- **Conclusion**: This statement is correct.

3. **Evaluate Statement B**:
- Chlorella and Spirulina are known to be used as food supplements, and they are indeed used as space food by astronauts due to their high nutritional value.
- **Conclusion**: This statement is also correct.

4. **Evaluate Statement C**:
- Manitol is a sugar alcohol that serves as a reserve food material primarily in brown algae (Phaeophyta), not in red algae (Rhodophyta). In Rhodophyta, the primary storage product is Floridean starch.
- **Conclusion**: This statement is incorrect.

5. **Evaluate Statement D**:
- Algin and Carrageenan are polysaccharides derived from algae, specifically brown and red algae, respectively.
- **Conclusion**: This statement is correct.

6. **Final Conclusion**:
- The wrong statement among the options is **C) Manitol is stored food in Rhodophyta**.

### Summary:
The wrong statement is option C, as Manitol is not the stored food in Rhodophyta; instead, Floridean starch is the storage product in red algae.