What type of message is typically found on service signs?

Service signs are designed to provide information about available services along the roadway, such as rest areas, food, gas stations, and lodging. These signs are usually blue in color and are strategically placed to help drivers locate essential services that can enhance their travel experience and safety. This ensures that travelers can plan stops as needed without detours, making their journey more efficient.

The other options refer to different types of signs found on the road. For example, the no parking allowed signs are regulatory and inform drivers about parking restrictions. Traffic diversion notices are typically part of traffic control devices that address current conditions affecting road use, while construction ahead warnings serve to alert drivers about roadworks that may alter traffic patterns or require reduced speed. Each of these signs serves a unique purpose, but they do not fall under the category of service signs, highlighting the specific role that these blue signs play in travel-related information.