到底选C还是D呀

到底选C还是D呀 线代行列式题,请问这个到底选C还是D 选c还是d 选C还是D 选C还是D. 选c还是d~ 这题到底选B还是C? 到底是选a还是c, 选d还是选c 应该选C 还是D 选c还是d啊 选c还是d?为什么? 选c还是d啊, 第四个选c还是D the last one ( )sings a song.---agreedA .arrived B.to arrive C .arrives D.arriving迷糊了~到底选B还是选D呐？纠结 ) weekends ,we often go to the zoo with parents.A.in B.at c.for d.on到底选B还是D? Many ____ trees should be planted on the mountains.A.thousand B.thousand of C.thousands D.thousands of 到底选A还是D Can he（）it in French?A.speak B.speaks C.say D.talk（到底应该选A还是C呢?为什么我觉得选A?）