Answer:
Political affiliation
Explanation:
Besides GPA, most four year colleges will also review your standardized test scores, community service, and extracurricular activities. The higher your scores are, and the more activities you participated in, the higher are your chances of being accepted by a certain college. Factors such as the number of hours of community services during high school (usually recommended from 50 to 200) may not be deciding but can make you stand out compared to other candidates, who do not have such accomplishments.
What colleges are not allowed to review is your political affiliation. It's not allowed for such factors and possible bias to affect your chances of admission.