Which structure connects the brain to the spinal cord?

The foramen magnum is the large opening located at the base of the skull, through which the spinal cord passes to connect with the brain. This anatomical structure is crucial because it allows for the continuity of the central nervous system, facilitating the transmission of neural signals between the brain and the body.

In contrast to the other options, the cranial cavity refers to the space within the skull that houses the brain but does not serve as a direct connector to the spinal cord. The nasal cavity is part of the respiratory system, involved in the intake of air and smelling, and has no role in connecting the brain and spinal cord. The temporal bone is one of the bones that comprise the skull and protects parts of the inner ear, but it does not lie directly in the pathway between the brain and spinal cord. Thus, the foramen magnum is the key structure that provides the link between these two crucial components of the nervous system.