What are the writing essentials of the Problem-solution Pattern mentioned in the video？

What are the writing essentials of the Problem-solution Pattern mentioned in the video？
A.Use some conjunctions.
B.The solution to the problems do not equals to the causes of the problems.
C.The solutions should echo the problems.
正确答案：Use some conjunctions.The solution to the problems do not equals to the causes of the problems.The solutions should echo the problems.