What action does the trapezius muscle NOT perform?

The trapezius muscle is a large, superficial muscle that spans from the base of the skull down the back of the neck and upper spine, extending out to the shoulder. Its primary functions include elevating the scapula (as in shrugging the shoulders), depressing the scapula (lowering the shoulders), and assisting in the rotation and fixation of the scapula during arm movements.

Flexing the elbow, however, is not an action performed by the trapezius. This action primarily involves muscles such as the biceps brachii and brachialis, which are located in the upper arm and specifically responsible for flexing the elbow joint. The trapezius does not have any connection or role in the flexion of the elbow, making this choice the correct response to the question. Understanding the specific functions of each muscle is crucial for grasping their roles in movement and biomechanics.