Every unit of classification regardless of its rank, is

Options

A. Taxon
B. Variety
C. Sub - species
D. Strain

Answer

**Step-by-Step Solution:**

1. **Understanding Classification**: Classification is a systematic process used to categorize living organisms based on their similarities and differences. This helps in organizing biological diversity.

2. **Identifying Taxonomic Ranks**: In biological classification, there are several hierarchical ranks. The main taxonomic ranks include:
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species

3. **Defining Taxon**: A taxon (plural: taxa) is any unit of classification in the biological hierarchy. Regardless of the rank, every unit is referred to as a taxon. For example, "Order" is a taxon, as is "Family" or "Species."

4. **Evaluating Options**: The question asks for a term that describes every unit of classification. The correct answer is "taxon," which encompasses all the ranks mentioned above.

5. **Analyzing Incorrect Options**:
- **Variety**: This term typically refers to a specific rank below species and is not a general term for all units of classification.
- **Subspecies**: Similar to variety, this is a rank below species and does not apply to all classifications.
- **Strain**: This refers to genetic variants, particularly in microorganisms, and is not a general classification term.

6. **Conclusion**: Based on the definitions and evaluations, the correct answer to the question is that every unit of classification, regardless of its rank, is called a taxon.

**Final Answer**: Every unit of classification, regardless of its rank, is a taxon.

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