Christina Aguilera -- Is a Hogan?

"The Voice" judge Christina Aguilera (left) -- and her Dirrty era extensions -- showed up to the American Music Awards nominations in L.A. on Tuesday ... looking like the long lost family member of Wynonna Judd Brooke Hogan (center) and Linda Hogan (right).

Hulk may have more 'splaining to do.

We're just sayin'.