What is the meaning and function of だというのか?


> じゃあ③が正解 **だってのか** よッ！

I know the bold part is jut a shortened version of だというのか. But what is the
meaning and function of だというのか? Is it just used to form an exclamation and it
means nothing?




「The link posted gives us that だというのか mean

> 「～～というのだ」、「～～というの」、「～～というのか」, etc. added at the end of a question generally
> functions to emphasize the question itself.
>
> By adding one of those phrases, you are expressing the fact that you really
> want to know the answer because whatever happened that caused you to ask the
> question perplexes, surprises, shocks you, etc.

So I would translate as :

> Is it really true ?

