Find the odd one out.

Options

A. Prawn and insects
B. Frog and snails
C. Snails and mussels
D. Prawn and mussels

Answer

To solve the question "Find the odd one out," we need to analyze the provided options based on their biological classifications.

### Step-by-Step Solution:

1. **Identify the Groups:**
- **Prawn and Insects:** Both belong to the phylum Arthropoda. Prawns are crustaceans, while insects are a separate class within Arthropoda.
- **Frog and Snails:** Frogs belong to the phylum Amphibia, while snails belong to the phylum Mollusca.
- **Snails and Mussels:** Both belong to the phylum Mollusca.
- **Prawn and Mussels:** Prawns belong to the phylum Arthropoda, while mussels belong to the phylum Mollusca.

2. **Analyze Each Pair:**
- **Prawn and Insects:** Both are arthropods but belong to different classes.
- **Frog and Snails:** These belong to different phyla (Amphibia and Mollusca).
- **Snails and Mussels:** These belong to the same phylum (Mollusca).
- **Prawn and Mussels:** These belong to different phyla (Arthropoda and Mollusca).

3. **Determine the Odd One Out:**
- The pair that stands out is **Frog and Snails** because they belong to entirely different phyla (Amphibia vs. Mollusca), while the other pairs involve organisms that are more closely related either within the same phylum or class.

4. **Conclusion:**
- The odd one out is **Frog and Snails**.

### Final Answer:
The odd one out is **Frog and Snails**.