Genus as unit of classficiation was first employed by

Options

A. Huxley
B. De Candolle
C. Tournfort
D. Linnaeus

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about who first employed the term "genus" as a unit of classification in biological taxonomy.

2. **Identifying Key Information**: The term "genus" is a taxonomic rank used in the biological classification of organisms. It is important to note who introduced this classification system.

3. **Historical Context**: The classification system that includes the genus was first developed in the 18th century.

4. **Identifying the Contributor**: The individual credited with first employing the term "genus" in this context is Carolus Linnaeus.

5. **Reviewing Options**: The options provided in the question include Huxley, D Candle, Turn Fort, and Lanius. Based on historical knowledge, we can eliminate Huxley, D Candle, and Turn Fort as they did not contribute to the introduction of the genus in classification.

6. **Final Answer**: The correct answer is Carolus Linnaeus, who first employed the term "genus" as a unit of classification.

7. **Conclusion**: Therefore, the answer to the question is option 4: Carolus Linnaeus.

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