—Your tea, please.

—There must be _____ in it. I like this kind of tea with sugar.  [ ]

A. sweet something    

B. nothing sweet  

C. something sweet    

D. anything sweet

部分电路欧姆定律的数字式是（）。

A.I=U/R

B.I=R/U

C.U=R/I

D.U=I/R