The basic/smallest unit of classification is

Options

A. (a) Species
B. (b) Taxon
C. (c) Category
D. (d) Subspecies

Answer

**Step-by-Step Solution:**

1. **Understanding Classification**: The question asks about the basic or smallest unit of classification in biological taxonomy. Taxonomy is the science of naming, describing, and classifying organisms.

2. **Hierarchy of Classification**: The classification system is organized into a hierarchy that includes seven main ranks:
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species

3. **Similarity Among Organisms**: As we move down this hierarchy from kingdom to species, the level of similarity among organisms increases. Organisms in the same kingdom are less similar compared to those in the same species.

4. **Identifying the Smallest Unit**: Among these ranks, the species is recognized as the smallest unit of classification. It represents a group of organisms that are very similar and can interbreed.

5. **Clarifying Other Terms**:
- The term "taxon" refers to any unit of classification, which can include any of the ranks (kingdom, phylum, etc.).
- "Subspecies" is a classification below species but is not considered the smallest unit.

6. **Conclusion**: Therefore, the smallest unit of classification is the species.

**Final Answer**: The basic/smallest unit of classification is **species**.

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