When can routine communications be resumed when radio silence has been imposed?

Correct Answer: Option C — Routine communications can resume after the Rescue Coordination Center transmits a message on the frequency or channel being used for emergency communications stating that such traffic has concluded.

Only the Rescue Coordination Center (RCC) managing the distress incident has the authority to declare the emergency traffic concluded. Once the RCC transmits the official 'Seelonce Feenee' or equivalent message, routine communications may resume on the frequency, ensuring that the emergency channel is not prematurely cluttered by non-essential traffic.