Multiple choice general knowledge Select the Odd one Out in the following words:- Bull Rhinoceros Unicorn Hippopotamus Reveal answer Fill a bubble to check yourself D Correct answer Explanation Hippopotamus is the odd one out because it's an amphibious mammal that lives primarily in water. Bull, Rhinoceros, and Unicorn are all land-dwelling mammals (unicorn being mythical). The hippo's aquatic lifestyle makes it distinct.