Answer:
The theory of the Comparative Advantage tells us that countries specialize in the production of those goods and services that they can produce at a lower opportunity cost than other countries.
Following this definition, we can say that the countries that have comparative advantage in the production of oil are those that either have a great amount of oil, or that have enough capital and human resources to produce a large amount of oil, even if they do not have as much oil itself.
Some of these countries would be Saudi Arabia, Qatar, Bahrein, Venezuela, and the United States.