Read the sentences and choose the option that best arranges them in a logical order.

a. Generally, it is unusual for a new problem in international relations to be considered without at the same time some international organization being developed to deal with it.
b. International society has, in spite of the diversity of culture and political systems, been progressively drawn closer together and become more unified.
c. Despite the fears and concerns of some governments that international organizations are increasing too fast and that they are a burden on their exchequers, they are still proliferating at a considerable rate.
d. People and their governments now look far beyond national frontiers and feel a common responsibility for the major problems of the world and for lesser problems that may subsist within smaller groups of states.
e. More recently in the 1990s the problems of international trade, which was growing increasingly complex, led to the development of the WTO.
f. For instance, concern with the instability of commodities markets led to the establishment in the 1980s of the Common Fund for Commodities and the competition for the newly discovered wealth of the international seabed area resulted in the creation of the ISA under the Law of the Sea Convention of 1982, based on the concept of the ‘the common heritage of mankind’.