[ My answer would be that the current scientific evidence is that the Earth is about 4.3 billion years old. However, it is not known what caused the Big Bang or how everything sprang from nothingness. Further, no scientist - not even Miles Degrasse Tyson in “Cosmos” - is able to explain how a self-replicating life form spontaneously arose from inorganic chemicals. ]
How about saying that thinking you know how old the earth is like being an orphan who was abandoned at a fire station with no note and claiming to know exactly who their parents are.
And then say does it really matter knowing when the planet was born?
“How old is the earth?”
“Dunno, I wasn’t there.”
Although science must recognize its limitations, it is not an answer to throw up your hands and say you don’t know, when the best scientific evidence is pointing in a certain direction.
And honestly, I would be wary of a politician who said that they rejected science in favor of the Bible on scientific issues. You can’t argue that the Bible is an absolutely correct scientific history, because you cannot empirically prove the Bible is anything more than a book.
I believe that the Bible is God’s Word. But, truth can be expressed by poetry and allegory as well as by a factual account.