Through which opening does the spinal cord exit the cranium?

The spinal cord exits the cranium through the foramen magnum, which is a large opening located at the base of the skull. This structure serves as a crucial passage for the continuation of the brainstem into the spinal cord. The foramen magnum not only allows for the connection between the central nervous system and the rest of the body but also provides a protective route through which the spinal cord can extend downward into the vertebral canal.

The cauda equina refers to a bundle of spinal nerves and spinal nerve roots that extend from the lower end of the spinal cord, but it does not serve as an exit point from the cranium. The foramen lamina does not exist as a standard anatomical term associated with the exit of the spinal cord; this term seems to be a misinterpretation or conflation of terms related to spinal anatomy. The vertebral foramen is the central opening in each vertebra where the spinal cord resides but does not represent an exit point from the cranial cavity.

Thus, the foramen magnum is the only correct answer when identifying the specific opening in the skull through which the spinal cord emerges.