Hi guys

I am planning to take the AP biology exam this May but I have’t taken AP biology at school because I live in Canada and we only have AP courses for seniors. Say if I don’t do well and get a 3, and I decide to withhold that score. Would the universities that I am applying to know that I took the exam but did not report the score? Or do they require all scores and do not allow score withholding? I am thinking about Hopkins and Penn. Thanks,