（）以来,配送在我国被证明为一种非常好的物流方式,在很多大城市建立了配送中心.
（）以来,配送在我国被证明为一种非常好的物流方式,在很多大城市建立了配送中心.
（） since then, distribution has been proved to be a very good way of logistics in China, and distribution centers have been established in many big cities.
A.1970s
B.1980s
C.1990s
D.year 2000
正确答案：1990s