Animals that can tolerate a narrow range of salinity are

Options

A. Stenohaline
B. Euryhaline
C. Exohaline
D. Endohaline

Answer

To solve the question regarding animals that can tolerate a narrow range of salinity, we will analyze the options provided and define the terms related to salinity tolerance.

### Step-by-Step Solution:

1. **Understanding the Terms**:
- **Stenohaline**: The prefix "steno-" means narrow, and "haline" refers to salt concentration. Therefore, stenohaline animals can only tolerate a narrow range of salinity. They are sensitive to changes in salt concentration.
- **Euryhaline**: The prefix "eury-" means wide. Euryhaline animals can tolerate a wide range of salinity levels. They are adaptable to both freshwater and saltwater environments.
- **Exohaline**: This term refers to organisms that are found in environments with high salinity, typically outside of their normal habitat.
- **Endohaline**: This term refers to organisms that live in environments with varying salinity levels but are not specifically defined in the context of narrow or wide tolerance.

2. **Identifying the Correct Answer**:
- Since the question specifically asks for animals that can tolerate a narrow range of salinity, we focus on the definition of stenohaline. Stenohaline animals, such as many freshwater fish, cannot survive in environments with high salinity due to their limited tolerance.

3. **Conclusion**:
- Based on the definitions and understanding of the terms, the correct answer to the question is **A. Stenohaline**.

### Final Answer:
**A. Stenohaline**

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