Sorry for my late reply but I was without Internet for a couple of days.
It’s easy to put too much emphasis on theories, in particular you might spend too much time explaining theories rather then applying them. Yet, the exam has got theories in its syllabus so they need to be referenced to some extent.
My suggestions are:
1 Consider a question on a common sense basis.
2 See of you can use a theory to analyse the situation in any way. Using theories or parts of them shows you have studied the syllabus and can help you organise the data and to deal with the issues using a recognised approach
3 Using theories where appropriate adds strength to your arguments.