Final answer:
The young man with critical injuries would have the best chance for survival with rapid transport to the hospital for advanced medical care.
Step-by-step explanation:
A young man with multiple injuries, including an unstable chest wall, numerous long bone fractures, and a large hematoma to his head, will have the BEST chance for survival if he is rapidly transported to the hospital. This immediate transportation is crucial to address his life-threatening injuries, which may include traumatic brain injury, internal bleeding, and potential complications such as hematoma expansion. While immobilizing his spine, controlling bleeding with a tourniquet, and administering pain medication are important, they are secondary to the immediate need for advanced medical care that can only be provided at a hospital.