When you meet some now words, you can ____ in your dictionary.

[      ]

A. look it up

B. look up it

C. look them up

D. look up them

下面哪一种设备属于GMDSS地面通信系统中进行遇险报警的方式（）。

A、NBDP

B、SSB

C、DSC

D、SART