B: "It was created out of absolutely NOTHING", you do not believe in true science since laws of Conservation of Mass do not allow matter and energy to be created from nothing.
Picking and choosing where to appear in this conversation, because I know I'm going to the mass-ninjaed anyway (ten pages in, this isn't even going to be the current argument, any more), but...
What if the universe is a zero-sum construct? Mass+Energy+Dark Mass+Dark Energy (if you believe in either/both the latter two) == 0, by all practical measurements.
Similar to how the (hypothetical) particle pairs can appear and disappear in the 'quantum foam', spontaneously, the universe could pop into existence in the 'Metaverse' foam, do its thing for umpteen billion years (by our measure... that is) and then dissipate/recollapse/annihilate with our anti-universe twin... So many different ways of looking at it. Loads of explanations. One might say a
pantheon of choices if one wanted to make such a metaphor.[1]
Personally I go for a different POV, though. The Universe is a static bubble in a timeless meta-void, the flow of time being represented by the 'latitude' as you slice through the multi-dimensional bubble in various ways. IOW: the universe just
is, and time is an illusion, much the same as consciousness is.
Again, an answer without proof. Unless we can make the same equivalent journey as a visitor from Flatland might to us. And we know that Mr Albert Square or Miss Victoria Line are lacking in the wherewithal to make the journey outside of their own dimension without external help, and even once they are disassociated they can only partly appreciate the extra-dimensionality, so should
we gain the ability to angle/translate our view beyond our own normal dimensions (and there are various reasons to assume we can not) it's still reasonable to assume that we could not definitively define the metaverse that we are then peeking into.
[1] Which one could stretch by saying that this would be something that we may never have the ability to experimentally check, so it remains inaccessibly high up the cosmic Mount Olympus and might as well be a group of gods and goddesses doing what they do, and having done what they have done, beyond the wit of mortal man... And some people will
believe in their own answer, while others may just tend towards one of the solutions, and others will get on with tilling the scientific fields (of which they do have direct experience, and can exert control over) of the plains below and Let Gods Be Gods and leave them largely unconsidered while trusting in their ploughs not to spontaneously turn into serpents
because there's no reason to consider that they might. But that's getting to be an increasingly complex analogy that probably satisfies no-one (including me).