① The book is mine.   ____     A. It's Mike's book.

② The book is Amy's.  ____     B. The book is theirs.

③ It's their book.   ____     C. Its' Amy's book.

④ The book is Mike's.  ____     D. It's my book.

“清理了野蛮的污浊，心灵才会漾起纯净的春波；扫除了愚昧析灰尘，思想才会绽放美丽析花朵。”这句话表明（    ）