Which of the following would not be an example of core musculature to stabilize the trunk and pelvis?

The pectoral group, which primarily consists of the pectoralis major and pectoralis minor muscles, is primarily responsible for movements of the shoulder joint, such as flexion, adduction, and internal rotation of the arm. While these muscles contribute to upper body movements, they do not play a key role in stabilizing the trunk and pelvis.

In contrast, the core musculature is primarily focused on maintaining stability and proper alignment of the spine and pelvis. The rectus abdominis and transverse abdominis are central to this function, as they support the spine and aid in maintaining intra-abdominal pressure. The latissimus dorsi, although known for its actions in the upper body, can also contribute to core stability through its connection to the lumbar spine. Thus, the pectoral muscles stand apart in this context, as they do not directly assist in core stabilization.