which relationship traversal function helps in accessing immidiate parent element?

Not surprisingly, .parent():
https://api.jquery.com/parent[^].

I wonder, did you get Read The Following Manual kind of responses before? ;-)

You really need to read documentation. Please, no offense. We really want to help you, and the best help would be to help you to stand on your own, at least in such trivial issues. I hope you haven't been banned by Google so far. :-)

—SA