Final answer:
Service signs are blue with white letters and symbols, which helps to distinguish them from other road signs and ensures they are easily recognizable by drivers.
Step-by-step explanation:
Service signs are typically designed to provide information to road users about amenities and other types of service facilities nearby, such as rest areas, hospitals, and gas stations. The correct answer to the question about the color and lettering of service signs is, Service signs are blue with white letters and symbols. This color scheme helps to distinguish these signs from other types of road signage and ensures they are easily recognizable by drivers.
It's essential for drivers to understand the meaning of different signs and symbols on the road to navigate safely and accurately to their destinations. Signage symbols can sometimes be unconventional or out of context, which might convey strong messages or be part of political and cultural statements as seen in some protests or college student attire decisions.