Hello there,
Sentence C misplaced the modifier and made the sentence confusing. To fix the sentence you can remove pool in the.
Hope I helped :)
<span>Gladwell argues that KIPP “has succeeded by taking the idea of cultural legacies seriously.” That means that a tradition like summer vacation is replaced with year-round schooling, and the times that the school day begins and ends changes as well as how students are instructed to pay attention in class.</span>