---We can use QQ to communicate with each other online.---Will you please show me?A. which

问题补充：

---We can use QQ to communicate with each other online.

---Will you please show me?

A. which to use

B. how to use it

C. what to use

D. where to use it

答案：

A. which to use

(答案→)B. how to use it

C. what to use

D. where to use it

解析：which to use用哪一个；how to use it如何使用它；what to use有什么；where to use it在哪儿用它。句意：我们能够用QQ在线相互交流。——你能告诉我如何使用它吗？结合语境可知选B。