All the categories used in classification of organism constitute:-

Options

A. Taxonomy
B. Systematics
C. Taxonomic hierarchy
D. Taxonomic affinity

Answer

To solve the question "All the categories used in classification of organism constitute:", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Classification**: Begin by recognizing that the classification of organisms is a systematic approach to organizing biological diversity. This involves categorizing organisms based on shared characteristics.

2. **Identifying Taxonomic Hierarchy**: The classification system is structured in a hierarchical manner, which is known as the taxonomic hierarchy. This hierarchy includes various levels of categories.

3. **Listing Taxonomic Categories**: The main taxonomic categories include:
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species

4. **Defining Taxonomic Category**: Each of these categories is referred to as a taxonomic category, which is a part of the overall system of classification.

5. **Choosing the Correct Answer**: The question asks for what all the categories used in classification constitute. The correct term that encompasses all these categories is "taxonomic hierarchy."

6. **Eliminating Incorrect Options**: The other options provided (taxonomy, systematics, taxonomic affinity) do not accurately represent the collective categories used in classification.

### Final Answer:
The correct answer is **taxonomic hierarchy**.

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