For puzzles on spotting an odd-one-out item in a list.
In an Odd-one-out puzzle, the objective is to find a pattern in a list and to notice that one of the elements deviates from this pattern.
Sheep, Shark, Dog, Rock, Chicken, Dog, Elephant, Parrot, Mouse, Worm, Frog, Snake, Trout.
In this case the answer would be
All other items in the list are animals.