Trochophore larva is a free swimming larva in

Options

A. Nereis, Aphrodite, Chiton
B. Nereis, Pheretima, Pontobdella
C. Tubifex, Bonellia, Hirudinaria
D. Pheretima, Lumbricus, Megascolex

Answer

To solve the question regarding the trochophore larva, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Trochophore Larva**:
- The trochophore larva is a type of larval stage that is free-swimming and is typically found in certain marine organisms.

2. **Identifying Characteristics**:
- Trochophore larvae are small, translucent, and have a distinct shape that allows them to swim freely in the water.

3. **Associating with Organisms**:
- Trochophore larvae are primarily associated with marine annelids. Annelids are segmented worms, and many of them have a trochophore stage in their life cycle.

4. **Examples of Marine Annelids**:
- Some examples of marine annelids that exhibit trochophore larvae include:
- Nereis
- Aphrodite
- Chiton (though Chiton is technically a mollusk, it is often mentioned in the context of trochophore larvae due to its similar larval stage).

5. **Conclusion**:
- Based on the information gathered, the correct answer to the question "Trochophore larva is a free swimming larva in" is related to marine annelids.

### Final Answer:
- The trochophore larva is a free swimming larva in marine annelids.