The basic smallest unit of classifications is :-

Options

A. Genus
B. Species
C. Order
D. All of the above

Answer

To solve the question regarding the basic smallest unit of classification, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Taxonomic Hierarchy**:
- Taxonomy is the science of classification of living organisms. The classification system is hierarchical, meaning it has different levels or categories.

2. **Identify the Taxonomic Categories**:
- The major taxonomic categories in order from largest to smallest are:
- Kingdom
- Phylum (or Division in plants)
- Class
- Order
- Family
- Genus
- Species

3. **Determine the Smallest Unit**:
- Among these categories, the smallest unit of classification is the **species**.
- A species is defined as a group of organisms that can interbreed and produce fertile offspring, and they are reproductively isolated from other groups.

4. **Evaluate the Options**:
- The options given are: genus, species, order, and all of the above.
- Since species is the smallest unit, the correct answer is **species**.

5. **Conclusion**:
- Therefore, the basic smallest unit of classification is **species**.

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

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