GWD-23-Q37求助~

wxq19881113

Until recently, trade flows were of interest mainly to economic experts and executives of large corporations, but since the past few years, the movement of goods and services across national boundaries have become the subject of intense public attention all over the world.
 E
A.    since the past few years, the movement of goods and services across national boundaries have become
B.    the movement of goods and services across national boundaries since the past few years became
C.    the movement across national boundaries of goods and services over the past few years have become
D.    over the past few years, the movement across national boundaries of goods and services are becoming
E.    over the past few years, the movement of goods and services across national boundaries has become
这个题很明显正确答案是E，（虽然我选成了A，看题失误）但是我不明白，over the past few years 和since the past few years有什么区别？到底是都对呢，还是since the past year是错的？？请大家指教！

雨中小熊呵

我决得since the past few years 应该不对吧  一般都是since1999什么的