If you change your hands from a position where they are pressed together to where they are cupped to collect a handful of water, you have mainly rotated which arm bone(s) ?

A) humerus
B) scapula
C) ulna
D) radius
E) carpels

The rotation of the hands from a position where they are pressed together to a position where they are cupped involves the rotation of the radius around the ulna. This action does not primarily involve the humerus, scapula, ulna, or carpals in terms of rotation. The radius and ulna are the two bones in the forearm, and the movement described is a function of the radius rotating to allow the hand to turn.