Which structure allows the spinal nerves to exit from the spinal cord?

Intervertebral foramen

Explanation:

These structures are found in between pairs of vertebrae and not only do spinal nerves pass through them, the spinal artery, veins, and transforaminal ligaments do too. While the spinal cord passes through the vertebral foramen, the spinal nerves exit and enter the spine through these intervertebral foramen to 'serve' the rest of the body.