I would call admissions and ask them. I know someone who was admitted to a school in Illinois, as an athlete on a half-scholarship, and he had a D in AP Calculus. He wanted to drop the class. They called the school and the school told them that he needed to stay in AP Calculus and get a C or better, or they would rescind his acceptance and scholarship. I know not all schools would respond in the same manner, but again, I would call admissions and ask them before dropping the course.