Step 1: Understanding the Concept:
The question asks to identify the geographical region with the largest quantity of "proven petroleum reserves." Proven reserves are the amount of oil that can be recovered with a high degree of certainty from known reservoirs under existing economic and operating conditions.
Step 2: Detailed Explanation:
While Venezuela (in South America) holds the largest proven oil reserves for a single country, the question asks about a broader region.
The region of West Asia, also commonly known as the Middle East, collectively holds the largest share of the world's proven petroleum reserves.
This region includes countries like Saudi Arabia, Iran, Iraq, Kuwait, and the United Arab Emirates, all of which are among the top ten countries for proven oil reserves.
The combined reserves of these West Asian countries far exceed those of other regions like East Asia, Russia, or the Americas.
Step 3: Final Answer:
The region with the world's largest proven petroleum reserves is West Asia (the Middle East). Therefore, option (D) is correct.