If free trade will benefit all nations in the long run, why do nations so often establish barriers, like tariffs, to make free trade impossible? Select one of the options below as your answer: A. Treaties forbid free trade. B. International organizations, like the World Trade Organization (WTO), forbid free trade. C. Nations often seek to protect their firms and their workers from competition. D. Nations fear that other nations will become too rich if they can trade freely.