GMAT Sentence Correction (SC) | Re: In 1713, Alexander Pope began his translation of the Illiad,

Notice the meaning of the sentence. It says He began some work and this work took him 7 years.

Therefore, Work took him 7 years MUST not happen before he began it. So, HAD is 100% incorrect here as it breaks the sequencing and conveys that the work took him 7 years and then he begun it.

I hope it makes sense.

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