I don't know why you're so concerned—it isn't your problem .
A. first of all
B. after all
C. all in all
D. in all
网友回答
A. first of all
(答案→)B. after all
C. all in all
D. in all
解析：此题考查短语辨析。after all“毕竟，终究”；in all“总共”；above all“最重要的是”；first of all“首先”。句意：我不知道你为什么如此担心，毕竟这不是你的问题。