What type of sign would indicate a school zone?

Answer: B — Yellow-green

A school zone is indicated by a yellow-green sign. This color is specifically chosen to signify areas where children are present and to promote driver awareness and caution. The yellow-green hue is more vibrant and stands out, catching the attention of drivers, which is crucial in areas with high pedestrian activity, especially children. This visual cue is part of the broader color system used in traffic signage to enhance safety. The other colors serve different purposes: orange is used for construction and detour signs, red is typically reserved for stop signs and yield signs to indicate prohibitive actions, and blue is used for informational signs related to services and facilities. Therefore, the use of yellow-green for school zone signs helps to ensure that drivers remain vigilant in areas where children may be crossing streets.