现代保险经营的数理基础是（）。

A.一人为众，众人为一

B.大数法则与概率论

C.保险费率的厘定

D.保险准备金的提存

When I came in, I found _____ .       [ ]

A. the glass breaking                      

B. someone breaking the glass

C. the glass broken                        

D. the glass being broken