The term taxon was first used by

Options

A. Meyer
B. Linnaeus
C. Lamarck
D. De Candolle

Answer

### Step-by-Step Solution:

1. **Understanding the Term 'Taxon':**
- The term 'taxon' refers to a group of organisms that share common characteristics. It is used in biological classification to categorize organisms based on shared traits.

2. **Identifying the Origin of the Term:**
- The question asks who first coined the term 'taxon'. This requires knowledge of historical figures in biology and taxonomy.

3. **Evaluating the Options:**
- The options provided are:
1. Meyer
2. Linnaeus
3. Lamarck
4. De Candole

4. **Analyzing Each Option:**
- **Meyer:** Adolf Meyer is credited with coining the term 'taxon'.
- **Linnaeus:** Known for developing the binomial nomenclature system for naming organisms, but he did not coin the term 'taxon'.
- **Lamarck:** A naturalist known for his early theories on evolution, not related to the term 'taxon'.
- **De Candole:** Important in plant classification but did not coin the term 'taxon'.

5. **Conclusion:**
- Based on the analysis, the correct answer is **Adolf Meyer**, as he was the first to use the term 'taxon'.

### Final Answer:
The term 'taxon' was first used by **Adolf Meyer**.

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