Which subject should I choose as my A level 4th subject?

I will be studying abroad in the UK next fall and this is my current choice of subjects for my A level:
Maths, Psychology, Biology and History.
Since I afraid history is going to be quite stressful(I only have studied history for 3 years in an 'easy' way), and I want to secure a straight A, which I don't feel confident with the presence of history, I would like to change it into something else.
So here is the question, should I choose a 'softer' subject or a traditional subject as my 4th subject? Which subject should I choose?

These are the subjects available at my school:
Art and Design, Art and Design: Critical and Contextual Studies, Art and Design: Photography, Art and Design: Textiles, Biology, Business Studies, Chemistry, Classical Civilisation, Computing, Drama and Theatre Studies, Economics, English Language, English Literature, Extended Project Qualification (EPQ), French, Geography, German, Government and Politics, Greek, History, Latin, Mathematics and Further Mathematics, Music, Physics, Psychology, Spanish and Theology.

I want to focus on 3 subjects as much as possible, but on the other hand I feel like the 4th subject can be equally important just in case one of the other three doesn't meet my expectation. I am really troubled by this now. Some useful advice will be much appreciated!! Thanks!!