It’s B but they are limited to how far back they can look based on discovery (or discovery by reasonable diligence).
And it’s not the ‘statute of limitation‘ which is an American term. It’s limitation period.
I don't think you can really have a go at me for using terms used and quoted in this thread. But I accept it is likely a general point for all.
If it is B, then what limits how far back they can go?