Trochophore larvais present in the development of

Options

A. Earthworm
B. Nereis
C. Leech
D. Frog

Answer

**Step-by-Step Solution:**

1. **Understanding Trochophore Larva**:
- Trochophore larvae are small, translucent, free-swimming larvae that are characteristic of certain marine organisms. They are typically spherical or pear-shaped and possess a ring of cilia known as the prototroch, which aids in swimming.

2. **Identifying Organisms with Trochophore Larvae**:
- Trochophore larvae are primarily found in the developmental stages of marine annelids and mollusks. This is crucial for identifying the correct option among the given choices.

3. **Analyzing the Options**:
- Option A: Arthrombe - Not a known organism associated with trochophore larvae.
- Option B: Nereus - This is a genus of marine annelids, which are known to have trochophore larvae.
- Option C: Leach - This does not correspond to a group known for trochophore larvae.
- Option D: Frog - Frogs are amphibians and do not have trochophore larvae.

4. **Conclusion**:
- Based on the characteristics of trochophore larvae and the analysis of the options, the correct answer is **Option B: Nereus**.

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