Find out the incorrect statements about the Rhodophyceae :-

Options

A. Majority are marine with greater concentrations found in the warmer areas
B. They are also found at great depths of oceans where relatively little light penetrates
C. Usually reproduce vegetatively by fragmentation
D. They reproduce asexually by biflagellate zoospores

Answer

To solve the question about the incorrect statements regarding Rhodophyceae, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Understanding Rhodophyceae**:
- Rhodophyceae, commonly known as red algae, are a class of algae characterized by the presence of red pigments, primarily R-phycoerythrin, which gives them their distinctive color.

2. **Analyzing the Statements**:
- **Statement 1**: "Majority are marine with greater concentrations found in the warmer areas."
- This statement is **true**. Most red algae are indeed found in marine environments, particularly in warmer waters.

- **Statement 2**: "They are also found at great depths of oceans where relatively little light penetrates."
- This statement is **true**. Red algae can thrive at significant depths in the ocean, where light penetration is minimal.

- **Statement 3**: "Usually reproduce vegetatively by fragmentation."
- This statement is **true**. Red algae often reproduce vegetatively through fragmentation, which is a common method of asexual reproduction in many algae.

- **Statement 4**: "They reproduce asexually by biflagellate zoospores."
- This statement is **false**. Red algae do not reproduce asexually by biflagellate zoospores; instead, they reproduce asexually using non-motile spores.

3. **Conclusion**:
- The only incorrect statement about Rhodophyceae is **Statement 4**: "They reproduce asexually by biflagellate zoospores."

### Final Answer:
The incorrect statement about Rhodophyceae is: "They reproduce asexually by biflagellate zoospores."

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