The third and fifth ones. They are relying on the ability of the search engine to understand human-like requirements. For any search engine, it should be easier to find a definition of a simple word, however, they are asking the whole question in order to obtain a more precise answer, maybe from a website that contains a similar question that has already been asked before.
Third and fifth students query the engine looking for a more specific answer that can fit their needs, so they don't have to do the analysis of information, just directly get the answer they need.
I'd go with B - Article. There are hundreds of good examples for the answer being B. For example, "a book" ('a' is an article - 'book' is a noun), "an apple" ('an' article - 'book' noun). Those are just the simple ones.
A dysfunctional relationship is one where two people make an emotional contract and agree to meet each other's needs in what end up being self destructive ways