________ the explanation of the book, we finally understood the meaning of the passage. [ ]

A. With the help of 

B. Under the help of

C. After the help of  

D. By the help of

我国森林火灾95%以上是人为引起的，引发森林火灾的人为用火可概括为两种：（）。

A.生产性用火

B.非生产性用火

C.上坟烧纸

D.农事用火