GMAT Critical Reasoning (CR) | According to a recent research study, more than 90% percent

IMO E.
90 percent of students graduating from private high school attend colledge
65 percent of those graduating from public high school attend college

Conclusion: parents should send their children to private school to increase the likelihood to attend colledge.

How to weaken this argument?

We need to find an answer that compare the public school with the private school and shows that students from public school will have chance to attend colledge not less than those from private school. only
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