Which of the following is NOT one of the main bones of the axial skeleton?

The pelvis is not considered one of the main bones of the axial skeleton. Instead, it is part of the appendicular skeleton, which includes the limbs and their associated girdles.

The axial skeleton is primarily composed of the bones that form the long axis of the body, which includes the skull, spine (vertebral column), and sternum (breastbone). These structures serve essential roles in protecting vital organs, supporting the body's structure, and providing attachment points for muscles.

Understanding the distinction between the axial and appendicular skeleton is critical for recognizing the roles these different sets of bones play in human anatomy and their implications in medical situations, especially in trauma and injury management.