An amphibian having gills in adult stage is

Options

A. salamander
B. aquatic frogs
C. Limbless amphibian
D. newt/mud puppy

Answer

To solve the question "An amphibian having gills in adult stage is," we will analyze the options provided and determine which amphibian retains gills as an adult.

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which amphibian retains gills in its adult stage. Typically, amphibians undergo metamorphosis and lose their gills as they transition to a terrestrial lifestyle.

2. **Analyze the Options**:
- **Option A: Salamander**: Not all salamanders retain gills in their adult stage. Some species do, but it is not a general characteristic of all salamanders.
- **Option B: Aquatic Frogs**: Frogs generally lose their gills during metamorphosis and do not have them in the adult stage.
- **Option C: Limbless Amphibian**: Limbless amphibians, such as caecilians, do not have gills in their adult stage; they are primarily terrestrial.
- **Option D: Newt or Mud Puppy**: The mud puppy, also known as a newt, belongs to the genus Necturus and retains its gills throughout its adult life. This is a key characteristic of this species.

3. **Conclusion**: After analyzing the options, the only amphibian that retains gills in its adult stage is the newt or mud puppy.

### Final Answer:
The correct answer is **D: Newt or Mud Puppy**.

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