How often should an anchored vessel's sound signal be repeated?

An anchored vessel must sound a signal to indicate its presence, particularly in areas where other vessels may be navigating. The rules specify that a vessel at anchor must make a sound signal every one minute. This frequency is intended to alert other vessels nearby of its position and to help prevent collisions, as vessels can drift due to tidal effects or wind. The sound signal typically consists of one short blast, which acts as a warning to other vessels in the vicinity. This routine signaling is crucial for maintaining safety in busy maritime environments.

The other options suggest either too frequent signaling, which could lead to confusion, or too infrequent signaling, which would reduce the effectiveness of the warning. The guideline of every one minute strikes an appropriate balance to ensure vessels remain informed while managing the potential for auditory overload.