Taxonomic keys are based on the

Options

A. Morphological characters
B. Reproductive characters
C. Anatomical characters
D. Contrasting characters

Answer

**Step-by-Step Solution:**

1. **Understanding Taxonomic Keys**: Taxonomic keys are tools used in biology for the identification of organisms. They help in distinguishing between different species based on specific characteristics.

2. **Identifying the Basis of Taxonomic Keys**: The question asks what taxonomic keys are based on. The options provided include morphological characters, reproductive characters, anatomical characters, and contrasting characters.

3. **Analyzing the Options**:
- **Morphological Characters**: These refer to the physical form and structure of organisms.
- **Reproductive Characters**: These involve characteristics related to the reproduction of organisms.
- **Anatomical Characters**: These are related to the internal structure of organisms.
- **Contrasting Characters**: This refers to the differences between two or more organisms that can be used to identify them.

4. **Determining the Correct Answer**: Taxonomic keys primarily rely on contrasting characters, which allow for a clear distinction between different species. Each step in a taxonomic key presents a choice between two contrasting options (known as a couplet), leading to the identification of the organism.

5. **Conclusion**: The correct answer is that taxonomic keys are based on contrasting characters.

**Final Answer**: Taxonomic keys are based on contrasting characters.

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