Final answer:
The vertebral regions from the closest to the head to the farthest are cervical, thoracic, lumbar, sacral, and coccygeal, in that order, which corresponds to answer choice (a).
Step-by-step explanation:
When putting the vertebral regions in order from the closest to the head to the farthest from the head, the correct sequence is cervical, thoracic, lumbar, sacral, and coccygeal. Therefore, the correct answer from the given options is (a) cervical, thoracic, lumbar, sacral, coccygeal. This order reflects the arrangement of the spinal regions in a lateral view of a human spine.
The cervical region consists of seven vertebrae, C1-C7, that form the neck; the thoracic region has twelve vertebrae, T1-T12, which connect to the ribs; followed by the lumbar region with five vertebrae, L1-L5, making up the lower back. The sacrum is formed by the fusion of five sacral vertebrae and is part of the pelvis. Finally, the coccyx, or tailbone, is created by the fusion of four small coccygeal vertebrae.