Who is the youngest Champion For this tittle?

[KeWilson]

Who is the youngest Champion For this tittle
-WWE Championship
-WWE World Heavyweight Championship
-WWE United State Championship
-WWE Intercontinental Championship
-WWE Tag Team Championship (both World Tag Team and WWE Tag Team Championship)
-WWE Women's Championship
-WWE Divas Championship

I think WWE World Heavyweight Championship is Randy Orton & WWE Championship is Brock Lesnar.

BQ- Who is the youngest Royal Rumber winner?