Cephalochordate Branchiostoma possesses

Options

A. Laterally compressed spindle-shaped body
B. Caudal fin
C. Dorsal and ventral fins
D. All the above

Answer

### Step-by-Step Solution:

1. **Identify the Organism**: The question asks about the characteristics of the cephalochordate Branchiostoma. Recognize that Branchiostoma is a member of the subphylum Cephalochordata within the phylum Chordata.

2. **Body Shape**: Branchiostoma has a laterally compressed, spindle-shaped body. This means that the body is flattened from side to side, giving it a streamlined shape.

3. **Fins**:
- **Caudal Fin**: At the posterior end of Branchiostoma, there is a caudal fin. This fin is broader and helps in propulsion.
- **Dorsal Fin**: There is a dorsal fin that runs along the mid-dorsal line of the body, extending from the anterior to the caudal fin.
- **Ventral Fin**: A shorter ventral fin is also present, which extends from the caudal fin towards the arteriopore, a median opening for expelling water.

4. **Conclusion**: Since Branchiostoma possesses a laterally compressed spindle-shaped body, a caudal fin, a dorsal fin, and a ventral fin, the correct answer to the question is "all the above."

### Final Answer:
Branchiostoma possesses all of the following: laterally compressed spindle-shaped body, caudal fin, dorsal fin, and ventral fin. Therefore, the correct option is "all the above."

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