Marina Exam Reviewer: How is "radio silence" imposed?

Marina Exam Reviewer:

How is "radio silence" imposed? 

A. It is imposed by the High Seas Service (HSS) controlling the distress communications on that frequency or channel 
B. By the On Scene Coordinator (OSC) 
C. It is imposed by the Public Correspondence Station (PCS) controlling the distress communications on that frequency or channel 
D. By the Coast Earth Station (CES) controlling the Distress communications on that frequency


Answer:      B. By the On Scene Coordinator (OSC) 

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