Mac: choosing Headphone as an output

I use a Mac Pro, mid-2010, and Audacity 3.13. Audacity sound won’t play out the headphones jack.I don’t see a way to choose Headphones as an output. iTunes plays out the headphones, but not Audacity, There is no “Headphones” option in the drop-down choices. Suggestions will be appreciated.

SOLVED: responding to myself. “Built-in Output” was what I had to choose. Sound now plays out from the headphone jack.