Algae can be found living in almost all parts of the world’s oceans

OE

The correct response is (B). This choice correctly uses the present-tense verb “allows” which agrees with the present-tense verb “are.” Additionally, it correctly places a comma before “which.”

If you chose (A), we need a comma before the word “which” to set it apart as a clear modifying phrase. The past tense verb “allowed” does not agree with the present tense verb “are” in the non-underlined portion of the second independent clause.

If you chose (C), no comma here before "which" means this choice is incorrect. We’ve also got a past perfect verb (“has allowed”) that conflicts with present tense “are” in the non-underlined portion of this sentence.

If you chose (D), remember the word “that” is restrictive meaning it is necessary to the meaning of the phrase, while "which" is not restrictive. The word “which” adds a sort of parenthetical note to a sentence.

If you chose (E), “water allowing” is unclear. We are missing a relative pronoun or a comma between “water” and “allowing.”

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