Spanish or Latin GCSE
Mainly because your second choice of subjects didn't include Mathematics, and if you can get a good grade in it, Maths can look very impressive on your UCAS form. Also because Geology and Geography are too similar, in my opinion.
This obviously would eliminate your choice of Astrophysics but unfortunately, at this point, you would have to eliminate some career groups.
I wouldn't advise a language A-Level normally, and I'm not familiar with Oxbridge's undergraduate schemes, but if you say that they "like" languages, then it's always good to have it.
Edit; Remember though, 5 AS Levels is quite difficult to get all A's in. It requires a lot of hard work, and most universities only ask for 3 A2's. Although I won't advise against it if you're willing to put in the work - many people do 5 AS Levels and manage to get AAAAA, thus leaving their uni subject options open, and obviously showing impressive academia.
Last edited by tsr-member; 09-10-2011 at 22:56.