What are the reasons that you can think of for the arthropods to constitute the largest group of the animal kingdom?

Explanation

### Step-by-Step Solution:

1. **Understanding Arthropods**: Arthropods are a phylum within the animal kingdom that includes insects, arachnids, myriapods, and crustaceans. They are known for their diverse forms and adaptations.

2. **Diversity and Numbers**: Arthropods make up more than two-thirds of all known animal species on Earth. This immense diversity is a key reason for their classification as the largest group in the animal kingdom.

3. **Jointed Legs**: One of the defining features of arthropods is their jointed legs. This anatomical structure allows for greater mobility and adaptability in various environments, facilitating their survival and proliferation.

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