JoeX said:

BREASTS DO NOT MAKE A RATING EXPLICIT.

Didn't tag it, but:

Explicit(in regards to nudity) - having sexual acts or nudity clearly depicted: explicit movies; explicit books.

I explicitly see breasts here and that is considered nudity. My understanding is that questionable is the step between actually showing something and not, like a provocative pose or provocative clothes.

Yes yes, I know this site does it differently. I've seen mods post the same thing but its odd and doesn't go with the word choice.