"Which programming languages support closures?" seems pretty straight forward and focussed?
That is, there is a clear question, a reference to what closures are (so there cannot be confusion), and a request for a fairly clear-cut answer.
Some background
Selecting the right language to develop an application in is incredibly important. Certain things are easily achieved in programming languages with closures that are not as elegantly/easily achieved in languages without.
It's therefore a consideration in the process of planning which programming language a software tool, library or application will be written in.
Question
How is this question in need of "more focus"?