Why is this the answer?

The answer is peacock because this clever riddle uses a fun word picture to describe a beautiful bird. Let's look at the clues. The first part says the creature has "two eyes in front." A peacock is a bird, and like most birds, it has two real eyes on its head so it can see where it is going. That clue is simple. Now for the tricky part: "a hundred behind." This is the part that makes you think really hard. The male bird, which we call a peacock, is famous for his amazing, giant tail. When he spreads his tail to show off for a female peahen, it is a magnificent sight. His tail is often called a train because it is so long and grand. If you look very closely at each long feather in his train, you will see a colorful, round design. This special design is called an ocellus, but it looks exactly like an eye. It is a big, circular shape with bright, shining colors inside. It truly looks like a beautiful eye staring right back at you. A peacock has so many of these long, flowing tail feathers that he can have many, many of these "eye spots" when his tail is fanned out. The riddle says "a hundred," and when you count all the colorful spots on a full, fanned tail, it really can look like a hundred eyes watching from behind him. The riddle is a smart way to describe the peacock's head and its incredible, feathery train all at once. It is a puzzle that tricks you into thinking those spots are real eyes, but they are just part of the feather's decoration.