How can you signal for help if you are stranded at sea?

Using a mirror to signal with sunlight or fire flares is the most effective method of signaling for help when stranded at sea. This approach utilizes a light source, such as the sun's reflection off a mirror, which can travel over significant distances and is easily visible to aircraft or vessels nearby. The intense, focused beam of light can attract attention from rescue personnel, even at great distances.

Flares are also an excellent tool for signaling distress because they produce bright, colorful light and smoke, making them highly conspicuous against the natural backdrop of the ocean and sky. They signal urgency and alert other vessels and rescuers to your situation, enhancing the likelihood of receiving assistance swiftly.

The other options, while they might seem like logical attempts to attract attention, are generally less effective. Shouting tends to be limited by distance and environmental noise, making it difficult for others to hear you over the sound of waves or wind. Waving your arms continuously might get someone's attention, but it is not as reliable or distinct as using reflective light or a distress signal flare. Throwing objects into the water does not effectively communicate distress and would not help in alerting others to your predicament.