【题目】It was officially reported that the first mammal ______ successfully from an adult cell was Dolly the sheep.
A. to be cloned B. having been cloned
C. to clone D. to have been cloned
在线课程【答案】A
【解析】
考查动词不定式一般式的被动式作后置定语。句意：据官方报道，第一只成功从成年细胞克隆的哺乳动物是多利羊。此处mammal和clone之间是一种被动关系，是动词不定式一般式的被动式作后置定语。故选A。