You earn this for successfully completing Test Chamber 1-1.
At the start of the game, you are trying to escape a facility and different paths are opening for you to escape and walls and other paths are closing around you, trapping and killing other clones. After a while, you end up back where you started and agree to test in the chambers. At this point, you can play Test Chamber 1-1. The chamber is pretty straightforward. Below is a video of me completing the chamber.*I did not see any notification saying the achievement unlocked. When I checked the Xbox App, it indeed was there, there was just no notification for it.