The correct answer is - A. an economic conflict and a conflict related to resources.
If two nations start to compete for a particular land for oil reserves, it means that they are most likely starting an economic conflict that is related to the natural resource that the oil is.
The oil is one of the most valuable natural resources, and every country wants to have as much of it as possible, so they use all means in order to get it. By getting more oil reserves, the economy of the country will became significantly stronger.
Unfortunately, the economic conflicts often lead to war, like it was the case with Iraq and Kuwait for example.
