I wonder can be done to get rid of my smoking.A how B which C what D when

问题补充：

I wonder can be done to get rid of my smoking.

A how B which C what D when

答案：

解析：考查宾语从句。宾语从句中缺少主语，故用what，how怎样，which哪一个，when当什么的时候，句意：我想知道做什么来戒烟。故选C。