During preventive control service, a controller will issue advice or instructions only under what condition?

• A. Always
• B. Never
• C. When pilot requests
• D. Only if a situation requires

Answer: (D)

In preventive control service, the controller’s role is proactive risk mitigation: provide guidance only when there is a situation that could affect safety or efficiency. That makes the option “only if a situation requires” the best choice. It captures the idea that advice is not given as a default, but issued to address a specific need—like a developing traffic conflict, deteriorating weather, or a timing/altitude constraint that could affect separation. If everything is proceeding normally, no extra input is issued. Pilots may still ask for information, but the defining rule is to act only when a situation requires.