Warehouse Chief Moke:
To qualify to become a Scavenger, your level must be at least 20 and you must pass the Test of the Scavenger. However, you haven't met either the level or the test requirement yet.
Hurry up and take the Test of the Scavenger, or go raise your level. Ask Collector Pippi of the Dwarven village about the test. She will tell you everything you need to know about it in detail. After you have passed the test and increased your level, come back to me. Then I will change your profession to a Scavenger.