“That was a ___ joke!,” Dana sputtered. Crossword Clue

 The answer to the crossword clue "That was a ___ joke!,” Dana sputtered" is RAD. This is a 3-letter word that means excellent, outstanding, or impressive.

In the context of the clue, Dana is using the word "rad" to express her disbelief that Ava would make such a bold joke. She is also using it to express her attraction to Ava, as she finds her confidence and humor to be very attractive.

The word "rad" is a slang term that was popular in the 1980s. It has since fallen out of favor, but it is still used by some people today.

I hope this helps!

By the way, the group that had a hit with "Sound of the Underground" is Girls Aloud.