All the books donated by the students from urban schools are said to the students in rura

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A. to be sent
B. being sent
C. having been sent
(答案→)D. to have been sent
解析：考查非谓语动词。从语法可知， be said 后面要接“不定式”，故排除B 项和 C 项，同时语意表示“捐的书几天前已被送往农村学生的手中了”，且send 和books 之间为动宾关系，故应用动词不定式的完成式的被动语态。答案选D 项。