Which of the following items is represented by a triangular road sign?

A triangular road sign is typically used to convey warnings or caution to drivers about potential hazards ahead. In this case, the correct choice indicating "Children crossing" aligns with the purpose of a triangular sign, as it alerts drivers to a significant risk for pedestrians, particularly children, in the area. Such warnings are crucial for road safety, prompting drivers to reduce speed and remain vigilant.

Mandatory turns, speed limits, and parking regulations, on the other hand, are represented by different shapes of road signs. Mandatory turns usually utilize circular signs, speed limits are often indicated by rectangular signs, and parking regulations are also conveyed through rectangles. Understanding the shape and meaning of traffic signs is essential for safe driving and maintaining awareness of road conditions.