What does a vigorous waving of one arm by a Rescue Swimmer (RS) typically communicate?

A vigorous waving of one arm by a Rescue Swimmer typically communicates that the individual is in trouble and requires assistance. This action is a well-established signal indicating distress and serves as a visual alert to nearby personnel, such as boat operators or other rescuers, that immediate help is needed.

This method of signaling is crucial in rescue scenarios, as it provides a clear and unambiguous indication of danger, distinguishing it from other actions which might convey readiness for other circumstances. The other choices relate to different contexts of engagement or operational readiness, but they do not specifically convey the urgent nature of distress signals like the vigorous waving of one arm does. Therefore, recognizing this signal is essential for effective and timely rescue operations.