高中英语The number of the students in senior high school,( )is m

as 还有“正如,正像”之意,表示说话人的依据、态度、评论和看法,常用在以下结构中：as we all know,as you can see/here/watch/remember/expect.as is often reported,as is known to us all,as has been said before,as often happens等.
as引导的非限制性定语从句课谓语主句前或后,也可在句中.
当先行词前有so/such时,如果关系代词在从句中作主语或宾语,那么只能用as.
例如：It is such a beautiful school as I have never seen before.
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B,非限制性定语从句

A

A
as 在这里指代整个主句，引导非限制性定语从句
能指代主句引导非限制性定语从句的还有which. 但如果和 is said/reported/announced/known 等连用带有“正如。。。。一样”的意思时，一般用as, 不用which

很明显，后句说的是前面提到的数字在增加中，我不知道对不对，但是如果是我的话，我会选B