Which set of animals belongs to the same phylum?

Options

A. Hirudinaria and Laccifer
B. Pila and Loligo
C. Obelia and Euspongia
D. Ophiura and Salpa

Answer

To solve the question of which set of animals belongs to the same phylum, we will analyze each option provided and identify the phylum for each animal mentioned.

### Step-by-Step Solution:

1. **Analyze Option 1: Herodinaria and Lysophora**
- **Herodinaria**: This organism belongs to the phylum **Annelida** (segmented worms).
- **Lysophora**: This organism belongs to the phylum **Arthropoda** (insects, arachnids, crustaceans).
- **Conclusion**: Since Annelida and Arthropoda are different phyla, this option is incorrect.

2. **Analyze Option 2: Phyla and Loligo**
- **Phyla**: This term seems to be a typographical error; it likely refers to **Pila** (a genus of freshwater snails), which belongs to the phylum **Mollusca**.
- **Loligo**: This is a genus of squid, which also belongs to the phylum **Mollusca**.
- **Conclusion**: Both belong to the same phylum (Mollusca), making this option correct.

3. **Analyze Option 3: Obelia and Euspongea**
- **Obelia**: This organism belongs to the phylum **Cnidaria** (jellyfish, corals, etc.).
- **Euspongea**: This organism belongs to the phylum **Porifera** (sponges).
- **Conclusion**: Since Cnidaria and Porifera are different phyla, this option is incorrect.

4. **Analyze Option 4: Ophiura and Salpa**
- **Ophiura**: This organism belongs to the phylum **Echinodermata** (brittle stars).
- **Salpa**: This organism belongs to the phylum **Urochordata** (tunicates).
- **Conclusion**: Since Echinodermata and Urochordata are different phyla, this option is incorrect.

### Final Answer:
The correct answer is **Option 2: Pila and Loligo**, as both belong to the phylum **Mollusca**.

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