Which one of these is exclusively marine chelone?

Options

A. Terrapins
B. Tortoise
C. Terrapins & Tortoise
D. Turtle

Answer

To determine which one of the options is an exclusively marine chelone, we will analyze each option based on their habitats.

### Step-by-Step Solution:

1. **Understanding Chelonia**: Chelonia is an order within the class Reptilia that includes turtles and tortoises. Members of this order are characterized by their hard shells.

2. **Identifying the Options**: The options provided are:
- Terrapins
- Tortoises
- Another type of turtle
- Marine turtles

3. **Analyzing Terrapins**: Terrapins are a type of turtle that primarily inhabit freshwater environments. Therefore, they cannot be classified as exclusively marine.

4. **Analyzing Tortoises**: Tortoises are land-dwelling reptiles that can be found in various habitats, from deserts to wetlands. They are not aquatic and thus cannot be considered exclusively marine.

5. **Analyzing Turtles**: Turtles, specifically marine turtles, are adapted to live in saltwater environments. They are primarily found in oceans and are rarely found in freshwater or on land.

6. **Conclusion**: Based on the analysis, the only option that is exclusively marine is the turtle. Therefore, the correct answer is **turtle**.

### Final Answer:
The exclusively marine chelone is the **turtle**.

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