The universe is extremely specific yet completely undetermined. So my answer is neither, we are not just randomly born out of nowhere in to a certain family but at the same time we are not specifically assigned and there is no reason for it.
This is just another case of somebody trying to sound deep and intellectual when in reality they are just dumb. But to throw a wrench into the convo, what about taking into account how your family and upbringing moulds who you become as a person?
This is a weird question I thought of. You can think about it in different ways really like the sperm that fertilized the egg had a lot of other sperms who would produce a slightly different combination, which one is "chosen"