@SS-I Never Well, just to disprove your answer: Your answer is correct in a biological-functionality perspective, but you should've probably taken into account the fact that the drawing is named "Drawing Hands" so-- :3 bro's quite fond of debates, but he's picky with peeps to debate with XD -___- as I was saying, your answer doesn't answer the written question. ...you done now? huh? :333 eh, I'm just ~idek hehe well, sorry if bro said anything wrong. He's not really that great at taking jokes XD
but tbh tho, bro being dense (Seriously?) is so adorable ^w^ *said anything "rude" aww, of course X3 *pets bro* -____-
To answer your question:
Hands work through the nervous system, through a bunch of veins which are connected to your brain and hand, and many other body parts.