>>>primarily the choice of the parents.
I think when you are that "high up" in the royal family then choice of name is NOT always down to the parents.
I am sure there are any number of names they CANT use, for all sorts of reasons (political, royal history etc)
I still think Elizabeth will be in their somewhere.
It is our Queens name, HER mothers name (the Queen mother), it is also the middle name of the Duchess of Cambridge AND her mother.
Calling her Diana would be an AWFUL choice.