Final answer:
At the time of "The Prize," a significant fraction of the world's oil reserves were located in the Middle East, estimated to be around 80% of the world's readily-accessible reserves.
Step-by-step explanation:
The fraction of the world's oil reserves that were in the Middle East at the time of "The Prize" can be understood from a geopolitical and historical context. During the early and mid-20th century, with the discovery of oil in Iran in 1908 and subsequent discoveries in other Middle Eastern countries, this region harbored some of the world's largest reserves. In the modern era, it is estimated that about 80% of the world's readily-accessible oil reserves are located in the Middle East. With respect to the geopolitical impacts, the Anglo-Persian Oil Company, now BP, was established to control production in Iran, and British interests in oil led to the creation of the Kingdom of Iraq under British mandate. These historical developments underscore the significance of Middle Eastern oil reserves from both a regional and a global perspective.