What does a blue sign indicate on the road?

Answer: B — Motorist services

A blue sign on the road signifies motorist services. These signs are designed to assist drivers by providing information about services available nearby, such as gas stations, food, lodging, and rest areas. The use of blue is a standard convention in road signage that communicates the presence of facilities that help improve the travel experience for motorists. Traffic regulations, construction zones, and speed limits are indicated by primarily different colors and formats of signs. For instance, regulatory signs often use red or white backgrounds, construction signs typically use orange, and speed limits are displayed on white signs marked with black text. Understanding these color conventions is crucial for safe navigation and compliance with road rules.