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.
Because neurones will not function properly neither will neuroreceptors if a person lacks neurotransmitters, these two parts (transmiters and receptors) all work together and depend on eachother.
Neurones are resposible for transmitting informations trought the body, and if neurotransmitters are no-existent, information may not be able to get to some body parts since neurotransmitters transmit the information.
Hope it helped,
Happy homework/ study/ exam!
It will be melt in the layer of earth called mantle because mantle has a higher temperature than crust. and as it melt, it will be called magma.