Maths is a decent choice for most science subjects. It won't really help you with the A-levels, but would be decent preparation for a science degree which can be (to varying degrees) more mathematical than their A-level counterparts.
That said, no choice is really a "wasted" choice if you get a good grade. So if you feel like you could do better at Geography, that could be a better fit for you.
I would definitely say that if you are unsure and have the opportunity to drop one down the line, that you should consider taking all 4. Then if you make the "wrong" decision for you (if one of them even is wrong for you), you won't have to drag through the rest of A-levels with a subject you don't like.