Which one of the following is the basic unit of classification?
(a) Species
(b) Genus
(c) Family
(d) Phylum

Options

A. Species
B. Genus
C. Family
D. Phylum

Explanation

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

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the basic unit of classification among the given options: Species, Genus, Family, and Phylum.

2. **Review Taxonomic Hierarchy**: Familiarize yourself with the taxonomic hierarchy, which is a system used to classify living organisms. The hierarchy typically goes as follows:
- Domain/Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species

3. **Identify the Basic Unit**: In the taxonomic hierarchy, the smallest and most specific unit is the species. It represents a group of organisms that can interbreed and produce fertile offspring.

4. **Evaluate the Options**:
- (a) Species: This is the smallest unit of classification.
- (b) Genus: This is a higher classification that includes multiple species.
- (c) Family: This is a higher classification that includes multiple genera (plural of genus).
- (d) Phylum: This is a higher classification that includes multiple classes.

5. **Conclusion**: Since the species is the smallest and most specific unit of classification, the correct answer is (a) Species.

### Final Answer:
The basic unit of classification is (a) Species.

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