Which muscle groups are primarily responsible for retracting the scapula?

The muscles primarily responsible for retracting the scapula are the rhomboids. These muscles, located between the scapulae and the vertebrae, work to pull the scapulae towards each other, facilitating proper posture and shoulder mechanics. The rhomboid major and minor are specifically designed for this function, enabling movements such as pulling and rowing, which emphasizes the retraction of the scapulae.

While the trapezius also plays a role in scapular movement, its functions are more varied, including elevation, depression, and rotation of the scapula, making its primary focus broader than just retraction. The latissimus dorsi and pectoralis major, on the other hand, are primarily involved in shoulder movements such as adduction and flexion, rather than directly facilitating scapular retraction. Hence, the rhomboids are the most directly involved in this specific action, making them the correct choice.