Largest amphibian is
(a) necturus
(b) ichthyophis
(c) crytobranches / andrias
(d) amphiuma

Options

A. necturus
B. ichthyophis
C. crytobranches / andrias
D. amphiuma

Answer

To determine the largest amphibian from the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the largest amphibian among the given options: (a) Necturus, (b) Ichthyophis, (c) Cryptobranchus/Andrias, (d) Amphiuma.

2. **Research Each Option**:
- **Necturus**: This is a genus of aquatic salamanders, commonly known as mudpuppies. They are not the largest amphibians.
- **Ichthyophis**: This is a genus of caecilians, which are limbless amphibians. They are also not the largest.
- **Cryptobranchus/Andrias**: This refers to the giant salamander, specifically the Chinese giant salamander (Andrias davidianus) and the Japanese giant salamander (Andrias japonicus). These are known to be the largest living amphibians.
- **Amphiuma**: This is a genus of aquatic salamanders known as amphiumas. They are not the largest amphibians.

3. **Identify the Largest Amphibian**: Among the options, Cryptobranchus/Andrias is recognized as the largest amphibian in the world, specifically the giant salamanders belonging to the family Cryptobranchidae.

4. **Select the Correct Answer**: Based on the information gathered, the correct answer is (c) Cryptobranchus/Andrias.

### Final Answer:
The largest amphibian is (c) Cryptobranchus/Andrias.

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