Branchiostoma is

Options

A. Filter feeder
B. Carnivorous
C. Omnivorous
D. Herbivorous

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about Branchiostoma, which is a genus of organisms belonging to the subphylum Cephalochordata.

2. **Understand the Habitat**: Branchiostoma is primarily found in marine environments. This information is crucial as it helps in understanding its feeding habits.

3. **Analyze Feeding Habits**: The feeding habits of Branchiostoma include consuming protozoans, algae, diatoms, and other organic molecules. This indicates that it feeds on small particles suspended in water.

4. **Determine the Feeding Strategy**: Given that Branchiostoma filters food particles from the water, it is classified as a filter feeder. This means it captures food particles from the surrounding water as it moves through it.

5. **Evaluate Other Options**: The other options provided (carnivorous, omnivorous, herbivorous) do not accurately describe the feeding habits of Branchiostoma, as it does not primarily consume larger animals (carnivorous), a mix of plant and animal matter (omnivorous), or only plant matter (herbivorous).

6. **Conclude the Answer**: Based on the information gathered, the correct classification for Branchiostoma is that it is a filter feeder.

**Final Answer**: Branchiostoma is a filter feeder.

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