The quality of EGC message is（）affected by the position of the ship, the time of reception and climatic condition.

单项选择题The information flow of the MSI broadcast must be controlled（）.

A.to avoid mutual interference
B.to keep silence
C.owing to the time-share nature
D.to regulate transmitter power

单项选择题If EGC receiver shares a same antenna with INMARSAT MES, it means that it can receive MSI（）.

A.from any INMARSAT satellite
B.via any appropriate Navtex and EGC station
C.via the satellite the MES is tracking
D.from any RCC and coast station

单项选择题EGC safetyNet transmits（）types of messages for mariners.

A.four
B.six
C.five
D.three

单项选择题However, reception of certain types of MSI messages, such as shore to ship distress alerts and navigational and meteorological warning are（）.

A.selective and can be suppressed by ships
B.mandatory and can not be suppressed by ships in the affected area
C.not very important so that ships don‟t require them
D.received by all ships wherever they are

单项选择题The International SafetyNet Service is able to address the call to（）.

A.all vessels
B.selected groups of ships
C.a particular ship
D.A, B, C are all right