Q. Maximum number of animals species belong to which among the following groups?
Answer: Arthropoda
Notes: Arthropoda is the largest phylum of animal kingdom because around 2/3rd of all the named species on Earth belong to this phylum. Ants, mosquitoes, flies, cockroaches, shrimp, crabs, spiders, scorpions etc. are examples of arthropods. There are three main classes of arthropods as follows:

• Insects: This includes mosquitoes, cockroaches, ants, flies, bees, moths, grasshoppers, beetles and butterflies
• Crustaceans: This includes crabs, lobsters, shrimp and barnacles
• Arachnids: This includes scorpions, spiders and mites

Further, a few other classes are onychophorans (velvet worms), diplopods (millipedes) and chilopods (centipedes).