I'd take an extra year if it's free.
If it's not free, then you'll have to see if can easily afford it.
If you can't easily afford it then I'd resit all of them next year.
Otherwise you will get overlooked in the application process when they see the AS Levels.
Personally, I would study Biology to A2 and drop Classical Civilisation instead as Biology is considered a hard Science. Consequently, unis will be drooling over you if you get a good grade.
However, I am not forcing you to do anything.
Remember don't give up and to fail to prepare is to prepare to fail.
Now a joke to make things more interesting:
-What's in the middle of Paris?
-An r.
"da dum chu"!