It honestly depends on what you're passionate about, and what you have an interest in. Generally, if you have a passion in a subject there is a higher likelihood of achieving better success in it. I do Geography, Politics, English and French as I would like to get into International Law in the future, but also because I find these pretty interesting. Of course, I'd recommend doing some research into what each course involves (look up the specification), making sure you find out which exam board your school does for each subject- prior research can help a lot and allow you to make a better, more confident decision.