I did bachelors with Botany, Zoology and Chemistry. which subject combination is okay?

Chemistry
International Relations (never studied but interested in it)
International Law (never studied but interested)
Geography (studied it before)

OR

Chemistry
Political Science
International Law (should there be Constitutional Law? instead of IL)
Geography

I am also thinking about dropping Chemistry wholly, because I'm more interested in subjects like global affairs and politics etc. So what should I do? Should keep science subjects (which I've studied before) or will it be fine to go for absolutely new subjects? (yup only if I can manage)