The study of genetic complement of an organism is known as:

Options

A. phylogeny
B. Genetics
C. palaeontology
D. Ontogeny

Answer

To solve the question "The study of genetic complement of an organism is known as:", we will analyze the provided options one by one to determine the correct answer.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the term that refers to the study of the genetic complement of an organism. The genetic complement typically refers to the complete set of genes or genetic material present in an organism.

2. **Analyzing the Options**:
- **Option A: Phylogeny**: This term refers to the evolutionary history and relationships among species. It does not pertain to the genetic makeup of an individual organism. Therefore, this option is incorrect.

- **Option B: Genetics**: Genetics is the branch of biology that focuses on genes, genetic variation, and heredity in organisms. It directly deals with the genetic complement of organisms, making this option a strong candidate for the correct answer.

- **Option C: Paleontology**: Paleontology is the study of fossils and ancient life forms. It does not involve the genetic study of living organisms, so this option is also incorrect.

- **Option D: Ontogeny**: Ontogeny refers to the development of an individual organism from the fertilization of the egg to its mature form. This term is related to developmental biology rather than the genetic complement, making it incorrect as well.

3. **Conclusion**: After analyzing all the options, we find that the correct answer is **Option B: Genetics**. This is the field that studies the genetic complement of organisms.

### Final Answer:
The study of genetic complement of an organism is known as **Genetics**.

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