—I have a toothache.           

—                     .[ ]

A. It doesn’t matter      

B. You should see a dentist

C. You should drink lots of water    

D. What’s the matter with you?

在光通信中，ODN1：32光分路器的损耗最大不超过：（）。

A.14db

B.15db

C.17.4db

D.18db