Which one of the following systems of classification assumes that organisms belonging to the same taxa have a common ancestor ?

Options

A. Earliest system
B. Artificial system
C. Natural system
D. Phylogenetic system

Answer

To answer the question, "Which one of the following systems of classification assumes that organisms belonging to the same taxa have a common ancestor?" we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking about a classification system that is based on the concept of common ancestry among organisms within the same taxon (group).

2. **Identify the Classification Systems**: The main classification systems we need to consider are:
- Artificial System
- Natural System
- Phylogenetic System

3. **Analyze Each System**:
- **Artificial System**: This system classifies organisms based on observable characteristics such as the number and shape of leaves. It does not consider evolutionary relationships or common ancestry.
- **Natural System**: This system classifies organisms based on natural affinities, considering both external and internal features. While it looks at relationships, it does not explicitly focus on common ancestry.
- **Phylogenetic System**: This system is based on evolutionary relationships and the concept of common descent. It assumes that organisms that belong to the same taxa share a common ancestor and focuses on how species have evolved over time.

4. **Conclusion**: Based on the analysis, the classification system that assumes organisms belonging to the same taxa have a common ancestor is the **Phylogenetic System**.

### Final Answer:
The correct answer is the **Phylogenetic System**.

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