Which of the following is not a feature of the brown algae?

Options

A. Multicellularity and large size
B. Almost exclusively marine
C. Attached forms have hold fast
D. Most common pigment is chl b

Answer

To determine which of the following is not a feature of brown algae, we need to analyze the characteristics of brown algae (Phaeophyceae) based on the information provided:

1. **Multicellularity and Large Size**: Brown algae are known for being multicellular and can grow to large sizes. This is a true feature of brown algae.

2. **Almost Exclusively Marine**: Brown algae are primarily found in marine environments, with very few species found in freshwater. This is also a true feature of brown algae.

3. **Attached Form with Holdfast**: Brown algae typically have a holdfast structure that anchors them to the substrate, which is another true feature.

4. **Most Common Pigment is Chlorophyll b**: This statement is incorrect. The most common pigments in brown algae are chlorophyll a and c, along with fucoxanthin, which gives them their characteristic brown color. Chlorophyll b is primarily associated with green algae (Chlorophyceae), not brown algae.

Based on this analysis, the feature that is not characteristic of brown algae is that "the most common pigment is chlorophyll b."

**Final Answer**: The most common pigment is chlorophyll b (this is not a feature of brown algae).

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