Answer
Answer: b. Extension
Extension is a movement that results in an appendage assuming a position at a greater angle from the body relative to that of its initial position. Such extensions are exemplified by the straightening of the the lower limb at the knee joint and by the straightening of the upper limb at the elbow joint
Work Step by Step
In rotation, the limb moves around its own axis.
In flexion -- example bending of the lower limb at the knee joint-- the angle between the appendage and the body is decreased; bending the forearm upon the arm at the elbow joint is also an example of flexion.
Pronation is the rotation of an anatomical structure towards the midline of the body. This movement is exemplified in the turning of the forearm and hand so that the palm of the hand faces downwards or backwards The foot can also be pronated.
Supination is the opposite of pronation. In supination of the upper limb the forearm and palm are turned upwards or forwards. The foot can also be supinated and pronated but these more confusing definitions because of the concepts of eversion and inversion.
Put simply, pronation of the feet is an inward rolling of the feet --ankles lean inwards; supination of the feet is an outward rolling of the feet--ankles lean outwards.
