Final answer:
The acromioclavicular joint (AC joint) is the shoulder joint that is assigned to the acromioclavicular joint ISS body region.
Step-by-step explanation:
The acromioclavicular joint (AC joint) is one of the shoulder joints that can be injured. This joint is formed by the articulation between the acromion process of the scapula and the acromial end of the clavicle. AC joint injuries, such as acromioclavicular separations, are assigned to the acromioclavicular joint ISS body region.