A: The three most important things that will guide you are these:
- What career you are interested in.
- Whether you have Core Maths as a subject or Maths Literacy. (The only other subjects which matter are Physical Science and Art).
- What your marks are, and particularly in Maths (and sometimes Physical Science) or Maths Literacy.
You can choose from these qualifications (200 in all).
Please see this article about Core Maths as part of your subject choice.
The best advice is to go through and download the prospectus/student guide which most institutions offer.
Note: you must try to get the one for the year you intend to study.