—Manypeopletalkabout"Didi".Ireallywonder

问题详情：

—Many people talk about "Didi". I really wonder ______.

—You call to order a taxi through it on your mobile phone easily.

                  A. how can I use them   B. who uses them most C. what they are used for

【回答】

C

知识点：宾语从句

题型：选择题