Correct option is E. Some beaches are frequently contaminated by
untreated sewage that flows into the ocean, which can last for several days.
Here, the reference of "which" is unclear: 'which seems to refer to the ocean which is illogical as the sentence means to say that it is the contamination that can last for several days in the ocean. Only E rectifies this error without creating any new error.
Untreated sewage may contain water; nutrients (nitrogen and phosphorus); solids (including organic matter); pathogens (including bacteria, viruses and protozoa); helminthes (intestinal worms and worm-like parasites) ; oils and greases; runoff from streets, parking lots and roofs; heavy metals
To learn more about untreated sewagr from given link
https://brainly.com/question/550175
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