You can use MSN to talk with Vivien on the Internet.I know. But can you tell me ?A

问题补充：

--- You can use MSN to talk with Vivien on the Internet.

--- I know. But can you tell me ?

A. when I can use it

B. what I can use it

C. why can I use it

D. how can I use it

答案：

(答案→)A. when I can use it

B. what I can use it

C. why can I use it

D. how can I use it

解析：考查宾语从句。tell后跟双宾语。宾语从句用陈述句语序，排除C、D；B项中的what是use的宾语，it多余。故选A。