After the update to COD a lot of newer guides and youtube videos are telling you to go A/B/C. Well B is easy to get into its one of the hardest to get out of. the updated guides are amazing but I would edit it slightly and go A/C then finish up with B so you don't have to get out you just need to pick up the last piece and trophy pops. With the COD update checkpoints don't work so you will need to get all 3 without setting any alarms and no resting or dying. hope this helps anyone who is having a hard time getting this after they fixed the old way!