Hydras, earthworms, grasshoppers, and humans are classified in the same:
A. Genus.
B. Species.
C. Phylum.
D. Kingdom.
Kingdom is the broadest category of which there are 5: Monera (bacteria and blue green alga), Protista (ameba, paramecium and alga), Fungi (mushrooms and yeast), Plants and Animals. All of these organisms are animals. The organisms are then broken up by phylum, class, order, family, genus and species.