Pop Quiz: Guess the Guns!

Flex your muscles and see how well you know Hollywood's buffest residents. By Cara Lynn Shultz

  • Which heartthrob showed off his buff biceps after a workout? | Zac Efron

CREDIT: Richard Beetham / Splash News Online

Published: Tuesday September 16, 2008 06:00 AM EDT

Which heartthrob showed off his buff biceps after a workout?