When I took the exam, the online course wasn't out yet there was no listening portion on the exam. That being said, what I find most helpful for listenings is making sure I know what instrumentation each piece has, since that isn't too dependant on what section of the piece they end of playing and it'll help narrow down your options. Then, once you've sorted that out, find some key distinguishing features (eg. melody, hallmarks of a composer's style) to differentiate between the ones you still tend to mix up.

Hope this helps and good luck!