it really depends on how motivated you would be and how good you are at the subjects. i have a friend who took all three sciences and maths last year and got AABB (and A*AA this year) so it is possible to do extremely well, but you have to really work hard. it also helps if you enjoy the subjects - im pretty sure that for medicine the only requirements that unis have are chemistry and biology, and you'll probably drop your fourth subject at the end of year 12 anyway so it's sort of irrelevant which one you choose. if you don't think you can handle physics just pick the one you'll get the best grade in, because that's essentially the most important thing - it would be better to have an A in english lit than a B or a C in physics. however, i would say that english lit is probably more of a facilitating subject than ICT, if you end up deciding between those two.