A library with five thousand books _____ to the nation as a gift.
A.is offered B.have offered
C.are offered D.has offered
请高手给个确切的答案,到底选什么,再讲下其中的语法知识,我将感激不尽,谢谢!
请高手见谅，我个人认为A和D都可以啊，为什么只能选D，而不选A呢？？？请高手为我讲解下，谢谢，我将感激不尽！！！