一道定语从句的单选题.scientist have made a new computer program_____allows the computer to cry out for help if someone has stolen it.A.who B.which C.what D.when为什么呢?为什么不是C

一道定语从句的单选题.scientist have made a new computer program_____allows the computer to cry out for help if someone has stolen it.A.who B.which C.what D.when为什么呢?为什么不是C
一道定语从句的单选题.
scientist have made a new computer program_____allows the computer to cry out for help if someone has stolen it.
A.who B.which C.what D.when
为什么呢?为什么不是C

一道定语从句的单选题.scientist have made a new computer program_____allows the computer to cry out for help if someone has stolen it.A.who B.which C.what D.when为什么呢?为什么不是C
what不能引导定语从句.你仔细看看就可以发现,其实what是不能引导从句的.
引导定语从句的关联词称为关系词,关系词有关系代词和关系副词.关系代词有that,which,who,whom,whose,as等；关系副词有where,when,why等.关系词常有3个作用：1,引导定语从句.2,代替先行词.3,在定语从句中担当一个成分.