Which of the following is a sign of a swimmer struggling in the water?

Uncontrolled thrashing is indeed a clear sign of a swimmer struggling in the water. When a swimmer is in distress, they may exhibit erratic movements and panic, which often manifests as thrashing and splashing in an attempt to keep their head above water. This behavior can be a result of fear or a lack of energy, and it indicates that the swimmer is not able to maintain control over their own movements or position in the water.

In contrast, calm breathing suggests that the swimmer is relaxed and in control, while consistent stroke technique indicates that the swimmer is effectively navigating through the water with a proper swimming form. Waving to the coach typically reflects a swimmer who is comfortable and seeking attention for a routine reason, rather than signaling distress. Recognizing the signs of distress, particularly the uncontrolled thrashing, is critical for ensuring the safety and well-being of swimmers.