BOTH INTERNATIONAL & INLAND A 200-meter vessel is aground in restricted visibility. Which signal is optional?

Correct Answer: Option C — A whistle signal

Rule 35(g) requires a vessel aground to sound the bell and, if 100 meters or more in length, the gong. The whistle signal (one short, one prolonged, one short) is an optional, additional warning to indicate position to an approaching vessel, but it is not a mandatory part of the primary signal.