（2010·重庆模拟）—Alice, you look puzzled．Haven’t you understood it?

—Yes．I _____of another problem just now． 

A．had thought

B．have thought

C．thought

D．was thinking

对进口家用电冰箱，报检人凭检验检疫机构出具的非氯氟烃制冷剂、发泡剂证明和《入境货物通关单》办理报关手续