Which one of the following statements is wrong.

Options

A. Algae increase the level of dissovledf oxygen in the immediate environment.
B. Algin is obtained from red algae, and carrageenin from brown algae.
C. Agar-agar is obtained from Gelidium and Gracilaria
D. Laminaria and Sargassum are used as food.

Answer

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

### Step-by-Step Solution:

1. **Statement Analysis:**
- **Statement 1:** "Algae increases the level of dissolved oxygen in the immediate environment."
- **Explanation:** Algae are photosynthetic organisms that produce oxygen as a byproduct of photosynthesis. Therefore, this statement is **correct**.

2. **Statement 2:** "Algin is obtained from red algae and carrageenan from brown algae."
- **Explanation:** This statement is incorrect. Algin is actually obtained from brown algae, while carrageenan is derived from red algae. The order of the sources is reversed, making this statement **wrong**.

3. **Statement 3:** "Agar-agar is obtained from Gelidium and Gracilaria."
- **Explanation:** Agar-agar is indeed obtained from red algae, specifically from the species Gelidium and Gracilaria. Thus, this statement is **correct**.

4. **Statement 4:** "Laminaria and Sargassum are used as food."
- **Explanation:** Laminaria and Sargassum are both types of brown algae that are cultivated and used as food. Therefore, this statement is also **correct**.

### Conclusion:
After analyzing all the statements, the **wrong statement** is the second one: "Algin is obtained from red algae and carrageenan from brown algae."

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