G4C10:What could be a symptom caused by a ground loop in your station’s audio connections?
Direct answer summary (2023-2027 NCVEC pool)
The official correct answer for G4C10 is You receive reports of “hum” on your station’s transmitted signal.
The key fact is You receive reports of “hum” on your station’s transmitted signal. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.