This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Upper limb bones and muscles (proximal region) & Scapular movements, Subject name: Anatomy
Retraction of scapula at sternoclavicular joint is done by: 
Select and explain. 
A. Serratus anterior, B. Trapezius, C. Subscapularis, D. Supraspinatus
B: Trapezius
Answer: B: Trapezius 
Explanation: Retraction means moving backward of scapula at sternoclavicular joint. It is done by the following muscles: Trapezius Rhomboid major Rhomboid minor. Subscapularis helps in medial rotation of humerus. Serratus anterior helps in protraction of scapula. Supraspinatus helps in adduction.