Final answer:
The extrinsic muscles of the trunk and neck include muscles that originate outside of the region and insert onto it, such as the sternocleidomastoid and trapezius.
Step-by-step explanation:
The extrinsic muscles of the trunk and neck are the muscles that originate outside of the region and insert onto it. These muscles are responsible for movements such as rotation and stabilization of the head and neck. Examples of extrinsic muscles in the neck include the sternocleidomastoid and trapezius, which are important for changing the position of the head and moving the neck.