Shirley _______ a book about china last year but I don’t kno

Shirley _______ a book about china last year but I don’t know whether she has finish it
A .has written B .wrote C .had written D .was writing

D .was writing
时间是last year,用过去时,排除A,C
而根据题意“I don’t know whether she has finished it(我不知道她是否已经写完)”,所以用进行时was writing,表示动作的持续,符合题意.而wrote表示“（过去）已写完”,与题意不符合.