The evolutionary history of an organism is known as

Options

A. Ontogeny
B. Phylogeny
C. Ancestry
D. Paleontology

Answer

To solve the question "The evolutionary history of an organism is known as," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**: We need to analyze the provided options: ontogeny, phylogeny, ancestry, and paleontology.

2. **Define Ontogeny**: Ontogeny refers to the development of an individual organism from the fertilized egg to its mature form. It focuses on the life cycle and growth stages of an organism, not its evolutionary history.

3. **Define Phylogeny**: Phylogeny is the study of the evolutionary history and relationships among individuals or groups of organisms. This term directly relates to the evolutionary history of an organism.

4. **Define Ancestry**: Ancestry refers to the lineage or ancestral background of an organism. While it relates to the evolutionary background, it is not specifically focused on the evolutionary history in a broader sense.

5. **Define Paleontology**: Paleontology is the study of fossils, which includes the history of life on Earth through the examination of fossilized remains. It does not directly define the evolutionary history of a single organism.

6. **Conclusion**: After analyzing all the terms, the correct answer to the question is **phylogeny**, as it specifically refers to the evolutionary history of an organism.

### Final Answer:
The evolutionary history of an organism is known as **phylogeny**.

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