Which one of the following is not a true amphibian animal

Options

A. Salamander
B. Toad
C. Tortoise
D. Frog

Explanation

To determine which of the following animals is not a true amphibian, we can follow these steps:

### Step-by-Step Solution

1. **Understand the Definition of Amphibians**:
Amphibians are a class of animals that typically have a dual life, meaning they can live both in water and on land. The term "amphibian" comes from the Greek word "amphibios," which means "both lives."

2. **Identify the Options**:
The question provides four options. We need to analyze each one to see if it fits the definition of an amphibian.

3. **Analyze Each Option**:
- **Salamander**: This is a true amphibian. It has a life cycle that includes both aquatic and terrestrial stages.
- **Toad**: This is also a true amphibian. Toads are adapted to live on land but return to water for breeding.
- **Frog**: Frogs are classic examples of amphibians, with a life cycle that includes both aquatic tadpole and terrestrial adult stages.
- **Tortoise**: Tortoises are reptiles, not amphibians. They have a hard shell and primarily live on land, with adaptations that are characteristic of reptiles.

4. **Conclusion**:
Based on the analysis, the tortoise is the only option that is not a true amphibian. Therefore, the correct answer is option 3: Tortoise.

### Final Answer
The animal that is not a true amphibian is the **Tortoise**.

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