S1:MAYDAY,MAYDAY,MAYDAY.This is MV Blue Sky.I have collided with an unknown object.I am sinking.Over. S2:MV Blue Sky,this is Eastern station.Report your position.Over. Q:What has happened to MV Blue Sky? A. She has run aground. B. She has collided with a ship. C. She has collided with an unknown object. D. She has struck an iceberg.