Some experts believe that the global economy is slowly recovering. The main evidence is that the U. S. economy has exceeded expectations and has performed well in terms of employment and housing; the European Central Bank has launched a financing operation plan to use relatively low-interest rates to lend, Many companies and SMEs have raised funds; the entire global commodity market has established sufficient confidence, so this is a very good sign. If the following are true, which of the following is most likely to be the prerequisite for the above argument? ['Experts have previously expressed no optimism about the U. S. economy.', 'European Central Bank submits the the original interest rate.', 'Economic conditions in non-European and American countries remain stable.', 'Lack of confidence in global commodity trading.']