The taxonomical unit exclusively used in the classification of animal kingdom is________.

Explanation

**Step-by-Step Solution:**

1. **Understanding Taxonomy**: Taxonomy is the science of classification of living organisms. It helps in organizing the vast diversity of life into categories that are easier to study and understand.

2. **Levels of Classification**: The classification of living organisms is structured in hierarchical levels. The main levels include: Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species.

3. **Focusing on the Animal Kingdom**: The question specifically asks about the classification within the animal kingdom. The animal kingdom is one of the five kingdoms in the biological classification system.

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