The Clue Hep chewing-gum action
The Answer POP
The answer "POP" fits the clue "Hep chewing-gum action" because it describes the sound made when you chew gum and it bursts. The word "hep" suggests something cool or trendy, and popping gum is often seen as a fun, youthful action. Additionally, "pop" is a common term used for the noise created when chewing gum, making it a perfect match for the clue.