Select an incorrect statement about red algae?

Options

A. they occur in well-lighted regions close to the surface of water
B. they occur at great depths in oceans where relatively little light penetrates
C. the red thalli of most of the red algae are multicellular
D. none of them have complex body organisation

Answer

To determine the incorrect statement about red algae, let's analyze the provided statements step by step:

### Step 1: Evaluate the First Statement
- **Statement**: "Red algae are found only in well-lighted regions which are close to the water surface."
- **Analysis**: This statement is incorrect because red algae are not limited to well-lighted regions. They can also be found at great depths in the ocean where light penetration is minimal. Therefore, this statement is not true.

### Step 2: Evaluate the Second Statement
- **Statement**: "Red algae are also present in the ocean's great depths where light penetrates comparatively less."
- **Analysis**: This statement is correct. Red algae can thrive in deeper waters, which have lower light availability.

### Step 3: Evaluate the Third Statement
- **Statement**: "Most of the red algae are multicellular."
- **Analysis**: This statement is also correct. The majority of red algae species are indeed multicellular.

### Step 4: Evaluate the Fourth Statement
- **Statement**: "None of them have complex body organization."
- **Analysis**: This statement is incorrect. Some red algae do exhibit complex body organization, with differentiated structures resembling roots, stems, and leaves, which is referred to as thallus.

### Conclusion
- After evaluating all statements, the incorrect statement about red algae is:
- **Option 4**: "None of them have complex body organization."

### Final Answer
The incorrect statement about red algae is **Option 4**.

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