Drawing on the writings of Thucydides, Niccolo Machiavelli, Thomas Hobbes and E. H. Carr, Morgenthau developed a realist theory of international politics in which he argued that “international politics, like all politics, is a struggle for power. Whatever the ultimate aims of international politics, power is always the immediate aim”. Morgenthau went on to argue that the basic feature of the international system is anarchy, and in this anarchic world, states can only rely on their own resources since under anarchy states cannot trust each other. Therefore, the correct option is B.