Any interpretation could be true. The reason there are so many is that QM is outside everyday experience, so we have no intuition to fall back on.
That said, my suggestion, and I know beginners and those with an interest in what QM is telling us don't like, is not to worry about interpretation until you understand QM to the level of a comprehensive textbook, such as Ballentine's QM: A Modern Development. Ballentine develops QM from just two axioms. And the second axiom actually follows from the first by what is called Gleason's Theorem. QM from just one axiom? Well, strictly speaking, there are seven rules (and a post on this forum discusses them), but they can be presented in a way that makes the others seem natural, which is what Ballentine does. In fact, an interesting exercise for advanced students is to find in the textbook where he uses those rules by the back door.
However, it is essential in understanding interpretations to realise that QM, at its core, is essentially just one rule (or axiom) and what that axiom is. In fact, you may, like I now do, say that QM is that one rule, plus some almost inevitable assumptions, and then evoke Newton's - I make no hypothesis. This becomes more attractive once you realise that every single theory makes assumptions not explained by the theory. I can provide a heuristic justification in the mathematical modelling sense for that rule (in mathematical modelling, when deciding the assumptions of our model, this sort of thing is often done), but I can't derive it; it must be assumed. However, the choice is yours to decide if this is satisfactory or not.
The second important thing is that QM is wrong. We know this because it predicts that the hydrogen atom is in a stationary state, meaning it should not absorb or emit photons. But we know it does. This is addressed by applying an extension of QM called Quantum Field Theory (QFT). However, the modern view of QFT is that it is the inevitable low-energy approximation of any theory at large distances that obeys well-established laws, such as Special Relativity. We have no choice. It is called Weinberg's Folk Theorem, and his advanced three-volume tome on QFT develops QFT from this view, which goes by the name Effective Field Theory (EFT). It even resolves, for energies we can currently probe, combining QM and GR, which, as you may have read, is a big problem. It is, but since we only know EFTs, all our theories have the same problem.
Where does this leave us in terms of interpretation? Basically, our most powerful theory is close to inevitable. To go beyond it, we need information from areas we can't currently probe (directly anyway). Sure, we can hypothesise (String Theory is one such attempt), but as of now, it looks like Einstein was right, QM is incomplete - but not for the reasons he thought. Still, one never knows - it may be the great man has the last laugh.
The answer to your final question is that, since we do not know the theory at the rock bottom of QFT (or even if there is one - it may be turtles all the way down - what a depressing thought - but nature is as nature is), we do not know. Gleason's Theorem suggests it is, but we do not know for sure.
Thanks
Bill
