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

**Step-by-Step Solution:**

1. **Understanding Red Algae**: Begin by defining red algae, scientifically known as Rhodophyta. These are eukaryotic organisms that are primarily found in marine environments.

2. **Characteristics of Red Algae**: Note that red algae do not possess centrioles or flagella, which is a distinctive feature of this group.

3. **Habitat of Red Algae**: Recognize that red algae can be found in various depths of water. They thrive in both well-lit regions close to the surface and at great depths where light penetration is minimal.

4. **Evaluating the Statements**: Analyze the provided statements about red algae:
- **Statement 1**: "They occur in well-lighted regions close to the surface of water." - This statement is correct.
- **Statement 2**: "They occur at great depths where relatively little light penetrates." - This statement is also correct.
- **Statement 3**: "The red thalli of most of the red algae are multicellular." - This statement is correct as well.
- **Statement 4**: "None of them have complex body organization." - This statement is incorrect because some species of red algae do exhibit complex body organization, which can include structures similar to stems, roots, and leaves.

5. **Conclusion**: Identify that the incorrect statement about red algae is the fourth one, which claims that none of them have complex body organization.

**Final Answer**: The incorrect statement about red algae is: "None of them have complex body organization."

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