Final answer:
The spinal column consists of 26 bones called vertebrae (option A), which include the 24 vertebrae plus the sacrum and the coccyx that have fused from originally more individual vertebrae.
Step-by-step explanation:
The spinal column consists of 26 bones known as vertebrae. The adult vertebral column is comprised of the 24 vertebrae, the sacrum, and the coccyx bones. The sacrum is typically made up of five vertebrae that have fused together to form one bone, and the coccyx usually consists of 3-4 vertebrae that have also fused into one bone. Over our lifespan, the number of vertebrae decreases from approximately 33 to 26 due to this fusion process. This structure is crucial as it surrounds and protects the spinal cord, supports the head, and serves as an attachment point for the ribs and the muscles of the back and neck.