Of the three animals, rhino is the herbivore. Rhinoceros, commonly known as rhino, is a large herbivorous mammal. Rhinos are known to feed on a wide variety of plant-based foods including grasses, leaves, stems, twigs, fruits, and flowers. They have a complex digestive system that enables them to extract maximum amounts of nutrients from plants.
On the contrary, owls and squids are not herbivores. Owls are carnivorous birds that feed on other animals, including rodents, insects, smaller birds, and fish. Squids are cephalopods, which feed on other marine animals, including fish, mollusks, and crustaceans. Both of these animals are predators and do not rely on plants for their nutrition needs.