Do you know _____? [ ]

A. when the train leaves the station

B. when does the train leave the station

C. when will the train leave the station

血袋标签确认时对冷藏后血液制品上的标签，应进行血袋与血袋之间、手指与标签之间进行摩擦，摩擦后标签上的油墨不得脱落。