求选矿比的公式是（）。

A．原矿量/精矿量

B．原矿品/精矿品

C．精矿品/原矿石

—What was the score of the match? Did you beat them?        

—________. We lost to the girls.       [ ]

A. Sorry, I don’t know    

B. I don’t want to talk about it        

B. It’s a secret            

D. Don’t ask