What does a triangular road sign with a red border typically signify?

Answer: C — Warning of a hazard ahead

A triangular road sign with a red border is universally recognized as a warning sign. This type of sign serves to alert drivers to potential hazards or changes in road conditions that could affect their safety. The triangular shape combined with the red border draws attention, which is crucial for conveying warnings effectively to motorists. Such signs might indicate things like sharp turns, pedestrian crossings, or other dangerous conditions that require drivers to exercise increased caution. In contrast, the other options correlate with different types of signs—information about upcoming services would generally be signs that provide directions or details without a triangular shape, the end of a speed limit zone is usually marked with a different sign shape, and direction to a nearby city is typically indicated with rectangular signs that guide rather than warn.