Water dog is :-

Options

A. Salamandra
B. Necturus
C. Alytes
D. Icthyophis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the identification of the term "water dog" among the given options.

2. **Analyzing the Options**:
- **Option 1: Salamander**: This is a type of amphibian known for its moist skin and preference for damp habitats. However, it is not commonly referred to as a "water dog."
- **Option 2: Necturus**: This is the correct answer. Necturus, commonly known as Mud Puppies, are aquatic salamanders that live in cold water with high oxygen concentrations. They have short gills that allow them to survive in oxygen-depleted water.
- **Option 3: Alitis**: This is incorrect. Alitis is commonly known as Mid White Dot and does not relate to the term "water dog."
- **Option 4: Ichthyophilus**: This option is also incorrect. Ichthyophilus refers to limbless amphibians and is not associated with the term "water dog."

3. **Conclusion**: Based on the analysis, the correct answer to the question "Water dog is:" is **Option 2: Necturus**.

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