Temperature and oxygen level
Protect the tree from animals, bugs, or other predators.
Sewage holds toxic microbes and contains a mixture of suspended impurities. When these impurities hit drinking water microorganisms begin to deteriorate the water, and uses up the dissolved oxygen with the microorganisms, making these water dangerous to drink from. Major impacts of this can include giardia, salmonella, cryptosporidium, and E. coli.
You must just analyze the words. Replication is a synonym of copy, so the only possible answer is C.
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