What is true about the spinal cord's passage through the lumbar spine?

The statement that the spinal cord does not pass through the lumbar spine is accurate. In fact, the spinal cord extends from the brainstem down into the vertebral column but typically terminates at the level of the first or second lumbar vertebra in adults, forming a structure known as the conus medullaris. Below this level, the spinal nerves continue down the vertebral canal in a bundle known as the cauda equina. Therefore, while the lumbar vertebrae are indeed part of the spinal column, the spinal cord itself does not traverse through them like it does in the cervical and thoracic regions.

By understanding this anatomy, it's clear why the other choices do not align with the correct information. The spinal cord does not pass through all lumbar vertebrae as it terminates before reaching them. It also does not have an enlargement specifically in the lumbar region—any enlargement occurs at the cervical region for the brachial plexus and at the lumbar region for the lumbosacral plexus, but the spinal cord itself does not enlarge in the lumbar area. Lastly, the protection of the spinal cord is primarily provided by the vertebrae and the spinal meninges, rather than by intervertebral discs, which serve