**Core Concept**
The rotator cuff is a group of muscles and tendons surrounding the shoulder joint, providing stability and facilitating movement. A common cause of rotator cuff injury is the compression of the underlying supraspinatus tendon by a nearby ligament.

**Why the Correct Answer is Right**
The supraspinatus tendon is often compressed by the acromion process of the scapula, particularly when the arm is elevated above 90 degrees. This compression can lead to chronic inflammation and tendon damage. The ligament most commonly implicated in this process is the coracoacromial ligament, which forms a ligamentous arch with the acromion process, potentially compressing the underlying supraspinatus tendon.

**Why Each Wrong Option is Incorrect**
* **Option A:** The glenohumeral ligaments provide stability to the shoulder joint but are not typically associated with rotator cuff injuries.
* **Option B:** The coracoclavicular ligament connects the clavicle to the coracoid process and is not directly related to rotator cuff injuries.
* **Option C:** The long head of the triceps tendon is a separate entity from the rotator cuff and is not typically implicated in rotator cuff injuries.

**Clinical Pearl / High-Yield Fact**
The coracoacromial ligament forms a "tunnel" that can compress the supraspinatus tendon, leading to rotator cuff injuries. This is a common mechanism of injury in overhead athletes, such as tennis professionals.

**Correct Answer:** C.