The signs for "understand" and "don't understand" use the same movement, orientation, handshape, and location. To distinguish between the two, what expression should you use to indicate the difference?
O move your head clockwise for "don't understand" and move your head counterclockwise for "understand"
nod for "don't understand" and shake your head for "understand"
O nod for "understand" and shake your head for "don't understand"
turn your head to the left for "understand" and turn your head to the right for "don't understand"