What does a blue road sign indicate?

Answer: C — Services like rest areas, gas stations, and hospitals

A blue road sign indicates services like rest areas, gas stations, and hospitals. This color is used to help drivers easily identify facilities that provide essential support on their journeys. For instance, if a driver needs to refuel, find food, or seek medical assistance, blue signs will help them find the nearest amenities quickly. These signs serve an important purpose in road safety and traveler convenience, guiding motorists to necessary services without confusion. In contrast, other sign colors and shapes are designated for different types of information, helping to create a standardized understanding of road signage for all drivers.