Why is this the answer?

The answer is mirror because this clever riddle describes exactly what happens when you look at your own reflection. Think about standing in front of a mirror in your bathroom or bedroom. When you step up to it, you can see yourself perfectly. The riddle says, "I look at you, you look at me," and that is what a mirror does best. It shows you a picture of yourself right back. You are looking at the mirror, and the reflection is looking right back at you. It is a magical pane of glass that shows your face, your clothes, and everything else in the room. Now for the tricky part of the riddle: "I raise my right, you raise your left." Try this right now if you can. Stand in front of a mirror and hold up your right hand. Which hand does your reflection hold up? It looks like the hand on its left side, doesn't it? The mirror seems to flip your body from side to side. When you wave with your right hand, your mirror-self seems to wave back with what looks like a left hand. This special kind of flip is what makes mirrors so interesting. A mirror does not actually swap your hands or feet. It just shows you a perfect, reversed image of yourself. Imagine a friend standing across from you. If your friend raises their right hand, it is on the same side as your left hand. The mirror acts just like a friend standing opposite you. It is a faithful helper for seeing your whole self, but it plays this one little trick by switching your sides. It is a cool piece of science and a great reason why the mirror is the perfect answer to the riddle. It is always looking at you and doing the opposite of your sides.