What is recognized as an international distress signal?

The correct response identifies flying the National Ensign upside down as an internationally recognized distress signal. This practice indicates a call for help and is traditionally understood among maritime and aviation communities. The display of a national flag in such a manner communicates to others that the entity is in dire need of assistance.

While flashing lights, firing flares, and sounding a horn can be effective means of signaling distress in particular contexts or situations, they are not universally recognized as international distress signals. Flashing lights, for example, may not carry the same connotation in every setting. Firing flares is often associated with urgent distress but is usually accompanied by specific conditions or contexts. Sounding a horn can serve as a warning or alert but does not carry the standardized meaning of a distress signal as recognized worldwide. Therefore, the act of flying the National Ensign upside down stands out as a distinct and widely accepted symbol of distress across various nations.