I was so happy with this question in the exam, it was so good.
Adding on to what
@yanujw said, absolutely tackle each part of the BoP, but be smart about it. If you must mention it and then don't really go that in depth about it, the examiner is gonna be thinking "what the hell". Rather, mention it, explain what it is briefly, then justify why you're giving it such little focus, i.e.secondary income, its a small and very technical component of the BoP, so doesn't have much of an effect.
This way, you demonstrate a deeper understanding of the content.