The answer that will complete the sentence is lack of
eutrophication. It is because eutrophication is considered to be important for
marine animals as this provides the bodies of water nutrients in which the
marine animals need and if they are lacking, the species composition may
change, the coral reefs may be destroyed, the oxygen that are dissolved are at
low level and what is more serious, dead zones can be formed in which the
ecosystem in the marine life may be destroyed or collapse.
C because I had the same question and my teacher said it was c
