乡、民族乡、镇政府预算的调整方案必须提请本级人民代表大会常务委员会审查和批准。（）

-Ten minutes ago, there __________ an eraser, a pen and some books on the desk.But now there __________ anything on it.

-Don't worry. Maybe someone put them away.

A. was, isn't   

B. were, isn't  

C. is, wasn't

D was, wasn't