Final answer:
The hypothesis is that Narrabeen Man may have been killed from afar, with evidence suggesting a skilled execution akin to old hunting techniques.
Step-by-step explanation:
The hypothesis regarding the demise of the Narrabeen Man suggests that he may have been killed from a great distance. This assumption is drawn from the examination of the injuries and tools used at the time. The method of killing would require a significant amount of skill and strength, akin to hunting procedures used on large animals, indicating the possibility of a targeted and planned execution rather than a close confrontation.