The correct answer is B) A red parachute flare. A red parachute flare is the most suitable option for night signaling to a ship on the horizon. Parachute flares are designed to burn brightly for an extended period and can be seen from a significant distance, making them highly effective for attracting the attention of nearby vessels at night. The red color of the flare is also easily recognizable as a distress signal. The other options, such as orange smoke flares (A), red handheld flares (C), and a flashlight (D), are not as well-suited for long-range night signaling. Smoke flares are primarily used during the day, while handheld flares and flashlights have a shorter range and may not be as visible to a distant ship.