有效单程票用布袋封装时存放于规定区域或文件柜，按每个布袋（）标准进行加封，对不满（）的零散有效单程票按照（）进行加封。

_____, I think, and the problems could be settled. [ ]

A. If you double your efforts

B. So long as you keep up your spirits

C. Making greater efforts

D. A bit more efforts.