A regional ecological unit having a specific climate is

Options

A. Biome
B. Landscape
C. Ecosystem
D. Biotic community.

Answer

To solve the question "A regional ecological unit having a specific climate is", we can follow these steps:

### Step 1: Understand the Options
We have four options to consider:
- a. Bio
- b. Landscape
- c. Ecosystem
- d. Biotic community

### Step 2: Analyze Each Option
1. **Bio**: This term typically refers to life or living organisms. It does not specifically denote a regional ecological unit with a defined climate.

2. **Landscape**: This refers to a portion of land that can include various ecosystems and does not have fixed boundaries. It is more about the physical appearance of an area rather than a specific climate.

3. **Ecosystem**: This is a community of living organisms interacting with one another and their environment. While ecosystems can have specific climates, the term is broader and does not specifically refer to a regional unit.

4. **Biotic Community**: This refers to a group of similar organisms living together in a specific area. It does not encompass the climate aspect.

### Step 3: Identify the Correct Answer
The term that best fits the description of "a regional ecological unit having a specific climate" is **Biome**. A biome is characterized by specific climate conditions and the types of plants and animals that thrive in that environment.

### Conclusion
The correct answer to the question is **Biome**.

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