Direct answer
Objectives follow journal display order. Some depend on your choices; follow the active objective in the game.
Result
A Novigrad merchant by the name of Sylvester Armello had hung a notice on the Novigrad board asking for help in tracking down a thieving imp. It seemed the merchants' guild was being pestered by a mysterious creature who kept stealing wares from its members stalls. Geralt accepted the job.
