A signal whistle's audible sound may be heard up to _____________ yards.

• A. 200 yards
• B. 800 yards
• C. 1100 yards
• D. 1500 yards

Answer: (C)

Audibility of a signal whistle depends on how loud the whistle is, how sound travels in the air, and the amount of background noise. Under typical boating conditions, a standard handheld signal whistle is designed to be heard at a substantial distance, and training materials commonly cite about 1,100 yards as the practical maximum. That makes 1,100 yards the best answer because it reflects the expected reliable range for a normal whistle when conditions aren’t unusually poor.

The other distances don’t fit as well: 200 yards is too short to be useful for signaling across a boat or in small craft traffic; 800 yards is plausible but represents a more conservative estimate than the commonly cited maximum; 1,500 yards would require exceptionally favorable conditions and a very powerful signal, which isn’t typical for a standard whistle.