题目内容：

The life people were used to _____ since the earthequake happened in Wenchuan.
A changed B.changing C.has changed D.having changed请告知理由谢谢

优质解答

选C.
句子中有个定语从句.The life是先行词.（that）people were used to是定语从句.这个定语从句省略了关系代词that.
关系代词that充当be used to的宾语.
自从汶川发生地震以来,人们过去所习惯的生活（方式）已经发生了改变.