What does a raised arm with a clenched fist signify?

A raised arm with a clenched fist is an internationally recognized signal used in rescue situations. This gesture communicates that immediate assistance is required. When someone raises their arm with a clenched fist, it signals to others that they are in distress and in need of help. This sign is crucial in emergency scenarios, as it allows rescue swimmers and other rescuers to quickly identify individuals who are in jeopardy.

In contrast, the other options do not accurately convey the message associated with a raised arm and clenched fist. For instance, "Proceed with caution" would typically involve more subdued hand signals or gestures that indicate vigilance without implying emergency. Similarly, "Resume activity" would not be represented by a clenched fist, as it implies normal operation rather than a need for aid. "Stop housing" does not relate to any recognized distress signal and does not convey any meaning regarding assistance. Therefore, the specific gesture of a raised arm with a clenched fist is unequivocally associated with needing help.