The sternocleidomastoid muscle extends from the mastoid process of the temporal bone to the sternum and medial clavicle. When both sternocleidomastoid muscles contract, the head is flexed. The end of the muscle that connects to the sternum is the ________.

A) origin
B) belly
C) body
D) insertion
E) fixator

Sternocleidomastoid Muscle

A muscle in the neck that runs from the sternum and clavicle to the mastoid process of the temporal bone, involved in the rotation and flexion of the head.

Sternal End

The end of a bone that is closest to the sternum, often referring to the ends of the ribs or the clavicle.

Insertion

The point or mode of attachment of a skeletal muscle to the bone or other body part it moves.