—I regretted what I have done.

—_______ gone is gone. ______ no use regretting it any more.[ ]

A. What's; That's    

B. It's; That's  

C. What's; It's  

D. That's It's

某中学地理兴趣学习小组在老师指导下沿甲图E～F、M～N作地形剖面图，成果分别为乙图和丙图。回答题。

①地比②地（）

A．海拔高，坡度大

B．海拔低，坡度大

C．海拔高，坡度小

D．海拔低，坡度小