[archy]

I pick number 3. The creation of West Virginia was Constitutional because the Virginia legislature that remained loyal to the Union, and which was recognized by Congress voted to create it.

Nope. Had that been the case, they would have been the government of the Unionist state of Virginia, USA, rather than a newly-formed state.

[Non-Sequitur]

Nope. Had that been the case, they would have been the government of the Unionist state of Virginia, USA, rather than a newly-formed state.

That would imply there were two Virginias. There was not, only a single state. And the duly recognized legislature of that state voted to split it in two.