单项选择题
Actually, the date for entry into effect will be 1st February（）.Though the text does not tell us about it.
A.1995 B.1998 C.1999 D.2000
单项选择题 The GMDSS must combine all various subsystems, because（）.
单项选择题 （）communication are intership VHF radio telephone communication.
单项选择题 The INMARSAT system is open for use by（）countries on a non-discriminatory basis.
