[单选题]MAYDAY,MAYDAY,MAYDAY. This is MV Pacific, Pacific,Pacific. call sign SUNO,SUNO,SUNO. Flooding is out of control. I am sinking. I will abandon ship in one hour. I am in position 23°25'N, 122°34'E. Over. 1:What's the vessel's call sign? A.SANL. B.SUNO. C.CANO. D.CUNL.