quEstions 18 to 20 ArE BAsED on thE Following pAssAgE.At thE EnD oF thE pAssAgE, you will BE givEn 15 sEConDs to AnswEr thE quEstions.
now, listEn to thE pAssAgE.
whAt is onE oF thE sourCEs oF thE oCEAniC sAlinityA．Erosion oF roCk mAntlE.
B．volCAniC Eruption nEAr CoAstAl ArEA、
C．DEAD BoDiEs oF mArinE liFE.
D、EvAporAtion oF rAin wAtEr.