The correct answer is C. It shows that this method is a disadvantage to those who need review at the beginning of the year.
This choice directly addresses the potential issue raised in the second source about students struggling if teachers spend too little time on review, which contrasts with the claims made in the first source that shorter breaks allow for better retention of information. Understanding this perspective enhances the reader's comprehension of the limitations and challenges that year-round schooling may present, particularly for students who may not benefit from the format.