单选题_____  the population of&

问题补充：

单选题_____,thepopulationofChinaisthelargestintheworld.A.It is known thatB.As is well knownC.Which is well knownD.We all know that

答案：

B解析众所周知，中国的人口在世界上最多。 as 引导的定语从句才能位于句首。