Organisms found in extreme temperatures are

Options

A. Eubacteria
B. Archaebacteria
C. Fungi
D. Mycoplasma

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about organisms that can survive in extreme temperatures. Here, "extreme" refers to both very high and very low temperatures.

2. **Identifying Temperature Ranges**: Normal body temperature is around 37°C. Extreme cold can be temperatures below 0°C, while extreme heat can be temperatures above 45°C or even up to 100°C in certain environments.

3. **Considering the Options**: The options provided are Eubacteria, Archaebacteria, Fungi, and Mycoplasma. We need to evaluate which of these can thrive in extreme conditions.

4. **Analyzing Each Option**:
- **Eubacteria**: These are common bacteria that generally thrive in moderate conditions and are not specifically adapted to extreme environments.
- **Archaebacteria**: These are known for their ability to survive in extreme conditions, including extreme heat (thermophiles) and extreme cold (psychrophiles).
- **Fungi**: Typically, fungi prefer moderate environments and do not thrive in extreme temperatures.
- **Mycoplasma**: These are a type of bacteria that lack a cell wall and are generally not known for surviving extreme temperatures.

5. **Conclusion**: Based on the analysis, the organisms that can survive in extreme temperatures are **Archaebacteria**. They are specially adapted to live in harsh environments, whether very hot or very cold.

### Final Answer:
**Archaebacteria** are the organisms found in extreme temperatures.

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