What is the main function of the skull?

The primary function of the skull is to protect the brain and support the structures of the face. The skull forms a rigid and protective encasement around the brain, safeguarding it from physical trauma and injury. Additionally, it provides structural support for the facial bones, which are essential for various functions, including respiration, mastication (chewing), and communication.

While other options pertain to aspects related to the skull, they do not encapsulate the main purpose as accurately. For instance, providing structure for the nervous system does relate to the skull’s enclosure of the brain, but it is more specific to the protective function rather than structural support. Similarly, assisting in the movement of the jaw is indeed a function related to the mandible and its articulation with the skull, but it does not represent the overarching purpose of the skull itself. Lastly, the idea of storing nutrients for brain function does not pertain to the skull's role, as the brain receives nutrients through the bloodstream rather than being stored within the skull.

Thus, the correct answer reflects the dual roles of protection and support, underscoring the significance of the skull in maintaining the integrity of the central nervous system and facial anatomy.