Translation:What is the nature of this relationship?
Maybe I'm missing something, but I can't figure out what this sentence is supposed to mean. I've never seen such a sentence before. (Maybe an overly direct translation from Polish?)
Maybe the sentence is a bit unfortunate and not obvious enough, but it almost certainly means a "związek" between two people, it's like asking whether they're dating or are just friends - and I cannot see "connection" put in such a context. So on the page you linked that would be (1.2) which is only translated as 'relationship'.
yes. There is this sentence in English for Polish course "I am going to the union"="Idę do związku" and the comment section is filled with rage because with no context Polish sentence seems ridiculous.
Relation/connection is other meaning that does not need much context, but doest not work with this sentence.