With the exception of the 12 cranial nerves, other major nerves exit the brain through the:

I think the answer should be medulla oblongata or foramen magnum.

The major nerves that leave brain should form a thick cord in the brain stem that called medulla oblongata. Medulla oblongata will pass a big hole in the base of the skull that called foramen magnum. Depends on what part the question asked(bone or tissue), it probably between those two options.

Ur very welcome for