An ecologist uses the term biodiversity for the variety of species of

Options

A. all living plants
B. all living animals
C. both (a) and (b)
D. (a), (b) and microbes also living in their natural habitats.

Answer

To determine the correct answer to the question about biodiversity, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Biodiversity**:
- The term "biodiversity" refers to the variety of life forms present in a particular habitat or ecosystem. This includes all living organisms, from plants and animals to microorganisms.

2. **Analyzing the Options**:
- **Option A**: All living plants - This option only includes one component of biodiversity.
- **Option B**: All living animals - This option also only includes one component of biodiversity.
- **Option C**: Both plants and animals - This option includes two major components but still does not encompass all forms of life.
- **Option D**: A means plants, B means animals, and microbes - This option includes all three major groups of life forms: plants, animals, and microorganisms.

3. **Conclusion**:
- Since biodiversity encompasses all living organisms, including plants, animals, and microbes, the most comprehensive answer is **Option D**.

### Final Answer:
- The correct answer is **Option D**: A means plants, B means animals, and microbes.

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