关于vi，下列说法正确的是（）。

A.vi有输入、指令和插入三种状态

B.更改文件后保存退出的命令是“：qw”

C.更改文件后保存退出的命令是“：wq”

D.更改文件后不保存，只退出的命令是“：q!”

One day after an appendectomy, a 9-year-old rates his pain at 4 out of 5 on the pain scale but is playing video games and laughing with his friend. Which of the following would the nurse document on the child’s chart（）

A. The child is in no apparent distress, and no pain medication is needed at this time.

B. The child rates pain at 4 out of 5. Pain medication administered as prescribed.

C. The child doesn’t understand the pain scale. Performed teaching to help child match his pain rating to how he appears to be feeling.

D. The child rates his pain at 4 out of 5; however, he appears to be in no distress. Reassess when he’s visibly showing signs of pain.