题干
I have some doubt ____ his words, but _______ is no doubt that he has passed the exam.
A：about; it
B：of; that
C：about; there
D：to; he
答案(点此获取答案解析）
C
A：about; it
B：of; that
C：about; there
D：to; he
，已知B、C、D、E、F五种烃有如下转化关系，B为苯的同系物，最多只有13个原子处于同一平面上，D中所有的原子一定在同一平面上．
