Answer: Students graduating from high school are not prepared for college-level work.
Explanation:
From the excerpt, it was written that there is a high rates of enrollment in remedial college courses which shows that there are many students are graduating from high school who are unprepared for college-level work.
Therefore, based on this, the best summary of the paragraph is that the students graduating from high school are not prepared for college-level work.
Therefore, the correct option is C.
