Which muscle group forms the chest region?

• A. Abdominals
• B. Pectorals
• C. Deltoids
• D. Rhomboids

Answer: (B)

The chest region is formed by the pectoral muscles, especially the pectoralis major, which spans the front of the rib cage from the sternum and clavicle to the upper arm. This large muscle gives the chest its bulk and shape and powers movements like pushing the arm forward or toward the midline. The pectoralis minor lies beneath it and helps with rib movement and stabilizing the shoulder blade.

Abdominals sit in the abdomen below the chest, forming the belly region. Deltoids are the shoulder muscles that create the rounded contour over the shoulder joint, not the chest. Rhomboids are upper-back muscles between the spine and shoulder blades, not part of the chest wall.