Question

The way he did it was different ___we were used to.

The way he did it was different__we were used to.
A.in which
B.in waht
C.from what
D.from which
为什么答案是c呢，我觉得d也对.

Answer 1

这个问题真好！
答案是c
注意这里是宾语从句不是定语从句。
The way (he did it) was different from what we were used to.
这里what we were used to 做介词from的宾语。
之所以用what不用which是因为：
what表示一个总体概念，它一般不用在有具体选择范围的句子中。
which则表示在一个具体的范围内进行选择。试比较：
I want to know what book you like to read. （总体概念）
I want to know whick book you like to read best of the three.
（在三本书里面选择）
What food do you like to eat?
Which food do you like to eat,fish or meat?(在两者中选择)

显然原句中的we were used to"我们习惯的（方式）"只是一个总体概念，故用what.

Answer 2

是C没错
这里的介词from是属于was different from这个词组
如果用D的话句子应该为：
The way he did it was different from the way
——we were used to。这里才要用in which

Answer 3

是选d答案错了吧，witch指the way，此空也可填from，that 顺便问一下，你这是几年级的英语呀

Answer 4

选d,前头有介词是应用which