Why is this the answer?

The answer is skin because this clever riddle describes your body's amazing outer layer in a very smart way. First, let us look at the first line: "When liquid splashes me, none seeps through." This is talking about how your skin is waterproof. If you pour a cup of water over your arm, the water just rolls right off. It does not soak in like it would on a towel or a sponge. This is super important because your skin keeps all the important things inside your body safe and dry, making it like a magical, personal raincoat for you all the time. The next clue is a little funny: "When I am moved a lot, liquid I spew." Think about playing tag or running around at recess. When you move and play hard, your body gets hot. To cool you down, tiny little holes in your skin called pores open up and let out sweat. That sweat is the liquid the riddle talks about. This natural cooling system is what stops you from getting too hot when you are active. The riddle continues with, "When I am hit, color I change." If you lightly tap your skin, it might turn a little pink. If you get a bump or fall down, the area might turn red or even blue later as a bruise forms. Your skin is always showing you what is happening underneath, which is a great way for your body to tell you if you are hurt. Another great clue is: "And color, I come in quite a range." Think about all the different people in the world. Their skin colors are all so different and wonderful. Some people have very light skin, and others have very dark skin, and there are many shades in between, which shows the great variety of human skin. Finally, the last part says, "What I cover is very complex, and I am very easy to flex." Your skin is covering your muscles, your bones, and all your organs, which is a very complex collection of things. But your skin is very stretchy, or "easy to flex," so you can bend, twist, dance, and move however you want without your skin ripping or holding you back. It is the flexible armor that keeps you protected.