I had another friend who received a scholarship to play golf at Arizona State. He got a D in Chinese (of all classes) and they were talking about revoking his scholarship/admission, but eventually he argued that his teacher was wrong and my high school administration backed him up.
The worst case was a friend who received a D in Spanish and was previously accepted to UC Santa Cruz. He had his admissions revoked and now he's studying at a community college in San Francisco while helping to coach our high school football team.
I don't mean to dishearten you at all, but understand that it's not a small deal. For universities, seeing a student slack off is a warning sign for things to come. The best thing to do is to go to your teacher and work something out...they understand that that kind of grade at this point in the year can often ruin a student's future. If that's not at all possible, talk to your guidance counselor and see if Rutgers is any different from the schools I mentioned from above. If you, you should be fine, but if not, then you might have to call the admissions people and explain yourself.