Is there any way to say either sentence is more natural?
A. ...most parents prefer their children to study abroad.
B. ...most parents prefer it for their children to study abroad.
B isn't natural at all.
A works, but it also works with the small addition of "for."
Most parents prefer for their children to study abroad.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.