Sentence Correction (SC) | Algae can be found living in almost

Algae can be found living in almost all parts of the world’s oceans; they are an important part of the world-wideecosystem by virtue of their constant re-oxygenation of the water which allowed them to rejuvenate even the most polluted environments.

A.by virtue of their constant re-oxygenation of the waterwhich allowedthem
Without comma which modifies water


B. by virtue of their constant re-oxygenation of the water, which allows them
Correct

C.on the grounds that their constant
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