NASA Photo ID: S69-34329, KSC-69PC-150
Date Taken: 05/13/69
The prime crew of the Apollo 10 lunar orbit mission sits for photograph while at the Kennedy Space Center for pre-flight training. Left to right are Astronauts Eugene A. Cernan, lunar module pilot; John W. Young, command module pilot; and Thomas P. Stafford, commander. In the left background is the Apollo 10 space vehicle on Pad B, Launch Complex 39, Kennedy Space Center. The three crewmen had just completed a Countdown Demonstration Test exercise.
Source: NASA photo in my possession