Hello! 
So I got accepted rice ed but my grades are honestly getting horrible…
and I might end up with 4 As 1 B and 1C (in ap calc bc).
Will these grades get me rescinded from rice? i’m so scared
1 C will not result in the rescinding of admission from any college. The other grades are fine. You definitely do not want any Ds on your transcript.
Given that your grades are not final, make an effort to bring that Calculus BC grade up to a B.
I feel so relieved! I will definitely try to raise my grades up a bit lol.
Thank you so much! 
@Hamurtle is right. You must be a very good student if you were accepted ED. Rice knows that a bit of senioritis sets in. If you were failing the course or didn’t graduate on time, that would be one thing. A C shouldn’t tank your admission. Try pulling your grade up and learning the course material. Get a tutor if necessary. My daughter got some tutoring for AP calculus. She ended up getting a good grade, a high score on the AP, and credit hours at Rice. If you make a 4 or 5 on the AP Calc BC exam, you could also get 6 credit hours for the course at Rice. https://registrar.rice.edu/sites/g/files/bxs751/f/2018%20-%202019%20AP%20EXAM%20LISTING.pdf Some Rice students are able to double major or take lighter course loads because of their AP credits.
Do you think I’ll even get a warning letter? 
Doubtful. What are your other classes? As @Houston1021 said, Rice is very generous with AP credit for a top school. You should make every effort to get at least a 4 on all your AP exams.