Poets,songwriters and politicians hate the idea,but for decades opinion-poll evidence has been clear:money buys happiness and the richer you are,the more likely you are to express satisfaction with your life.Until now,a survey of 43 countries（1）on October 30th by the pew Research Cenre of Washington,DC,shows that people in（2）markets are expressing almost the same level of satisfaction as people in rich countries.It is the biggest（3）to the standard view of happiness and income seen（4）The Pew poll asks respondents to（5）,on a scale from zero to ten,how good their lives are Those who say between seven and ten are counted as（6）.In 2007,57%of respondents in rich countries put themselves in the top four tiers;in emerging markets the（7）was 33%:in poor countries only 16%-a classic（8）of the standard view But in 2014,54%of rich-country respondents counted themselves as happy,whereas in emer-ging markets the percentage（9）to 51%.This was happening just at a time when emerging markets chances of converging economically（10）the West seemed to be（11）Rich countries did not experience（12）declines in happiness.The decreases in America and Britain were tiny（a single percentage point）,13 the share of happy Germans rose（13）points.A large drop in formerly joyful spain ensured a modest overall decline for the rich.（14）the conver-gence happened（15）huge improvements in countries such as Indonesia and Pakistan.In 12 of the 24 emerging markets,half or more people（16）their life satisfaction in the top tiers of the ladder.This is not to（17）the link between income and satisfaction has been snapped Poor coun-tries still（18）only a quarter of the people there are in the happy tiers=half the level of the other two groups.There is（19）a clear link between happiness and income growth.China's GDP rose at an annual average rate of 10%in 2007-2014 and its happiness level rose 26 points.（20）countries,richer people express more satisfaction than their poorer neighbours.wing onilia（13）选？

• A.because
• B.since
• C.while
• D.when