Re C, the justification is that with the current parliament there is no chance of no deal going through unless it is explicitly demanded by the public in a clear vote.
If you believe that there is no chance of an acceptable deal for Leave voters (I fail to see how anyone can think that will happen given what we've been through) and that therefore the only Leave option is no deal and you want to leave the EU, I'm not sure I understand why you wouldn't support the referendum I described.
Rightly or wrongly, it's your only chance of getting what you want.