Which one of the following is the largest phylum in the animal kingdom?

Options

A. Annelida
B. Arthopoda
C. Chordata
D. Protozoa

Explanation

**Step-by-Step Solution:**

1. **Understanding Phyla in the Animal Kingdom**: The animal kingdom is divided into various phyla, each representing a major group of animals that share certain characteristics.

2. **Identifying the Largest Phylum**: Among the various phyla, we need to identify which one has the largest number of species.

3. **Analyzing the Phylum Arthropoda**: The phylum Arthropoda is known to include a vast diversity of species. It encompasses insects, crustaceans (like prawns and lobsters), arachnids (like spiders), and more.

4. **Species Representation**: It is estimated that approximately 80% of all living animal species belong to the phylum Arthropoda, making it the largest phylum in terms of species count.

5. **Comparing Other Phyla**:
- The second largest phylum is Mollusca, which includes snails, clams, and octopuses.
- The third largest is Chordata, which includes vertebrates and some invertebrates with a notochord.

6. **Conclusion**: Based on the analysis, the phylum with the largest number of species in the animal kingdom is Arthropoda.

**Final Answer**: The largest phylum in the animal kingdom is Arthropoda.

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