The correct answer is B) oil refining.
The other options of the question were A) gold mining. C) cattle ranching. D) automobile manufacturing.
Advances in oil refining would have the greatest impact on Nigeria's economy.
Nigeria has oil reserves and the government of this country has been slow to decide to open the oil industry to private companies and foreign investors in order to exploit this valuable raw material. For whatever reasons that go from nationalistic to protective views, Nigeria has not been able to completely open this important industry to private capitals to maximize production and increase trade opportunities.