They'll arrive at nine, we know.
A.as much as B.as many as C.as little as D.as long as
They'll arrive at nine, we know.
A.as much as B.as many as C.as little as D.as long as
A:差不多 B:和……一样多(修饰可数名词) C:和……一样少 D:只要
所以最佳选A
选A 意思是:和我们知道的差不多
as long as 是“只要”的意思,不能选。