I'm torn between skin and water. I know that the skin is the largest organ in the body, but I am really not sure if that is the answer. It is either water or skin. If I find that I am wrong, I will come back and post the correct answer. Sorry I wasn't of much help!! I know how frustrating school (and especially Biology) can be!!
Skin is the largest organ in the body, but water make up about 60 % of your body. So water is your answer!