Organisms restricted to narrow range of temperature are

Options

A. Steno thermal
B. Biothermal
C. Eurythermal
D. Geothermal

Answer

To solve the question "Organisms restricted to narrow range of temperature are?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about organisms that can only survive within a narrow range of temperatures. This is a key concept in ecology and biology, particularly in understanding how organisms adapt to their environments.

2. **Identifying the Types of Organisms Based on Temperature Tolerance**: Organisms can be categorized based on their temperature tolerance into two main groups:
- **Stenothermal Organisms**: These organisms can tolerate only a narrow range of temperatures.
- **Eurythermal Organisms**: These organisms can tolerate a wide range of temperatures.

3. **Analyzing the Options**:
- **Option A: Stenothermal**: This option refers to organisms that can only tolerate a narrow temperature range. This fits the definition we are looking for.
- **Option B: Biothermal**: This term relates to heat produced by biological processes and does not pertain to temperature tolerance. Thus, this option is incorrect.
- **Option C: Eurythermal**: This option refers to organisms that can tolerate a wide range of temperatures, which is the opposite of what we are looking for. Therefore, this option is incorrect.
- **Option D: Geothermal**: This term refers to organisms found in geothermal environments, such as hot springs, and does not relate to temperature tolerance in the context of narrow ranges. Hence, this option is incorrect.

4. **Conclusion**: Based on the analysis, the correct answer is **Option A: Stenothermal**. These organisms are indeed restricted to a narrow range of temperature.

### Final Answer:
Organisms restricted to a narrow range of temperature are **Stenothermal**.

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