Final answer:
The cauda equina is located within the vertebral column and is composed of lumbar, sacral, and coccygeal nerve roots that extend from the lower end of the spinal cord.
Step-by-step explanation:
The cauda equina is located within the vertebral column. Specifically, it is a bundle of spinal nerves and spinal nerve rootlets, consisting of the second through fifth lumbar nerve pairs, all the sacral nerve pairs, and the coccygeal nerve, which arise from the lumbar enlargement and the conus medullaris of the spinal cord. This structure resembles a horse's tail, which is the translation of 'cauda equina' in Latin, and it extends from the lumbosacral spine down through the vertebral canal. The correct answer to the student's question is E) within the vertebral column. Cauda equina is vital for transmitting nerve signals to and from the legs, pelvis, and bowel.