What is the proper punctuation mark, if there is such a thing, to use in this kind of sentence?
What is the proper punctuation mark (if there is such a thing) to use in this kind of sentence?
What is the proper punctuation mark – if there is such a thing – to use in this kind of sentence?
What is the proper punctuation mark ... if there is such a thing ... to use in this kind of sentence?
comma
the en dash is a little dramatic and the others are just wrong
All but the last one imo