Could be any of those things, but give it a few days to see if it goes away before you go nuts trying to scrub everything off. If your wheels stay dry and you drive the car it may go away without you spending time money and energy to fix it. You at least won't be any worse off.
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2022 Macan S
2016 F31 328i xDrive Sport Wagon
2006 E46 330ci ZHP Convertible
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