GMAT Sentence Correction (SC) | Re: A recent study has found that within the past few years,

Sure.

As per this rule, we can have either "to both X and Y" or "both to X and to Y".

Notice, in the first one I kept to outside once and this would be used for both X and Y while in the second one, I used to with both X and Y. Hence, in the letter part we have Twice Inside.

Here are the great questions that work on the same principle.

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