Good Genes Or Good Docs?!

Nick Carter's looks over the years are your one desiiiiire!

Here is a fresh-faced Nick posing at 14 years old for a Backstreet Boys photoshoot -- looking oh so bold with his bowl cut in NYC back in 1995 (left). This was just a few years before the boy-bander's hit song "I Want It That Way" became a worldwide banger!

And, nearly 3 decades later Mr. Carter -- who's celebrating his 44th birthday today -- recently snapped a sweet selfie showcasing those baby blues mid-flight!

Yes, his angles are still hittin' just right, but the question here is ...