Final answer:
The Rhomboid major muscle produces scapular retraction, pulling the shoulder blades towards the spine. The correct option is B.
Step-by-step explanation:
The muscle responsible for scapular retraction is the Rhomboid major. Scapular retraction occurs when the scapulae move towards the spinal column.
The muscle that produces scapular retraction is the Rhomboid major. When the rhomboids are contracted, they pull the scapula medially, resulting in scapular retraction.
These muscles are located on the posterior thorax. The Rhomboid major and its companion muscle, the Rhomboid minor, are located in the posterior thorax, and they work together to pull the scapulae medially towards the spine.
This action contrasts with muscles such as the Serratus anterior, which are involved in scapular protraction. The correct option is B.