Which signal equipment is required for a vessel 100 meters or more under Inland and international rules?

• A. A whistle
• B. A bell
• C. A horn
• D. A gong

Answer: (D)

When a vessel reaches 100 meters or more, the signaling equipment requirements expand to ensure clear audible communication in busy or foggy conditions. In addition to a whistle, large vessels must carry a bell, and they also must have a gong. The gong provides a distinct, longer-duration signal that complements the whistle and helps other vessels hear and recognize the vessel’s presence and intentions in challenging conditions. This specific instrument is required for vessels of this length class under both Inland and International rules, which is why the correct choice is the gong.