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

Correct option is D

The Correct Answer is: (d) Arthropoda

Explanation:
Arthropoda is the largest phylum in the animal kingdom, comprising more than 80% of all known animal species. This phylum includes insects, arachnids (spiders, scorpions), crustaceans (crabs, lobsters), centipedes, and millipedes. Arthropods are characterized by a segmented body, jointed appendages, and a chitinous exoskeleton. Their adaptability, complex behaviors, and reproductive strategies have enabled them to inhabit a wide range of environments – from deep oceans to mountaintops and even deserts.

Information Booster:
• Phylum Arthropoda includes more than 10 lakh (1 million+) known species.
• Insects alone (class Insecta) make up the majority of arthropods.
• Arthropods have an open circulatory system and a ventral nervous system.
• Their body is divided into three main parts: head, thorax, and abdomen (especially in insects).
• Exoskeleton made of chitin provides protection and prevents water loss.
• They undergo molting (ecdysis) to grow, shedding the old exoskeleton.
• Economic importance: Some are pests (e.g., locusts), vectors (e.g., mosquitoes), while others are useful (e.g., honeybees, silkworms).

Additional Information:
•  Chordata – Includes animals with a notochord, such as mammals, birds, reptiles, amphibians, and fish. It is not the largest phylum.
• Annelida – Segmented worms like earthworms and leeches. They are fewer in number compared to arthropods.
• Mollusca – Second-largest phylum; includes snails, octopuses, squids, etc. Soft-bodied animals, often with a calcium carbonate shell.