I'd say if you get Bs, then take them.
What grade are you predicted to get? How did your exams go?
If they're your best subjects and you're motivated, you should be okay
Besides, there are lots of people on here (myself included) who would be very, very happy to help you out
If you'd like a future career in science, it's your only
option - so just make sure you work hard
As long as you're committed, motivated, and keep on top of everything (organisation is key!) - you'll be fine
I took Bio, Chem, Maths & Eng Lit for As
Feel free to ask me any questions