隋朝灭亡的标志性事件是[ ]

A. 瓦岗军攻占洛阳            

B. 山东长白山农民起义爆发

C. 李渊称帝                  

D. 隋炀帝在江都被部将杀死

He didn’t tell us_________.

A．if he will give us a lecture

B．whether he would go with you

C．when he was started

D．when he will arrive