What is the anatomical term for the last (inferior) part of the vertebral column?

The last part of the vertebral column is called the coccyx, which is also commonly referred to as the tailbone. It is located at the inferior end of the vertebral column and consists of three to five fused vertebrae. The coccyx provides support for a person when sitting and serves as an attachment point for various muscles, tendons, and ligaments, which contribute to pelvic stability and posture.

The other options represent different regions of the vertebral column. The pelvis refers to the bony structure located at the base of the spine, supporting the trunk and containing the pelvic organs, but it is not part of the vertebral column itself. The lumbar region consists of the five vertebrae in the lower back and is located above the coccyx. The thoracic region includes the twelve vertebrae of the upper and mid-back that articulate with the ribs. Thus, these regions do not describe the most inferior part of the vertebral column, making the coccyx the correct anatomical term.