The fundamental taxonomic category or basic unit of classification is

Options

A. Genus
B. Species
C. Sub-species
D. Variety

Answer

**Step-by-Step Solution:**

1. **Understanding Taxonomic Categories**: Taxonomy is the science of classification of living organisms. It involves various levels of classification, known as taxonomic categories.

2. **Identifying the Fundamental Unit**: The question asks for the fundamental taxonomic category or basic unit of classification. The smallest and most basic unit in this hierarchy is the species.

3. **Defining Species**: A species is defined as a group of organisms that can interbreed and produce fertile offspring. They share a high number of common characteristics, which makes them distinct from other groups.

4. **Analyzing Other Options**:
- **Genus**: A genus is a group of species that are closely related. While it is a taxonomic category, it is not the fundamental unit.
- **Subspecies**: This refers to a further division within a species, which is also not a fundamental unit.
- **Variety**: This term is often used in botany to denote a specific form of a species, but it is not a fundamental taxonomic unit.

5. **Conclusion**: Based on the definitions and classifications, the correct answer to the question is "species," as it is the fundamental taxonomic category.

**Final Answer**: The fundamental taxonomic category or basic unit of classification is **species**.

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