Organisms that are restricted to a narrow range of salt concentration are termed

Options

A. 1)euryhaline
B. 2)stenothermal
C. 3)eurythermal
D. 4)stenohaline

Answer

To answer the question, "Organisms that are restricted to a narrow range of salt concentration are termed," we will analyze the options provided and determine which one correctly describes such organisms.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about organisms that can only survive within a narrow range of salt concentration. This is a specific ecological term related to salinity.

2. **Analyzing the Options**:
- **Option 1: Urea heline**: This term refers to organisms that can tolerate a wide range of salinity, not a narrow range. Therefore, this option is incorrect.
- **Option 2: Tenothermal**: This term refers to organisms that require a narrow range of temperatures to survive. It is not related to salt concentration. Thus, this option is also incorrect.
- **Option 3: Urethermal**: This term indicates organisms that can tolerate a wide range of temperatures. Again, this is not related to salt concentration, making this option incorrect as well.
- **Option 4: Tenohaline**: This term specifically refers to organisms that are restricted to a narrow range of salt concentration. This aligns perfectly with the question.

3. **Conclusion**: After evaluating all the options, the correct answer is **Option 4: Tenohaline**. These organisms are indeed restricted to a narrow range of salt concentration.

### Final Answer:
The organisms that are restricted to a narrow range of salt concentration are termed **Tenohaline**.

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