What does a yellow diamond-shaped sign indicate?

Answer: B — Warning of potential hazards ahead

A yellow diamond-shaped sign indicates a warning of potential hazards ahead. These signs are used to alert drivers to specific conditions that may require caution. This can include things like sharp turns, intersections, pedestrian crossings, or changes in the road surface. The yellow color itself is a universal sign of warning, while the diamond shape is specifically used to signify that something unexpected may be on the road. The other choices represent different types of signs. A stop ahead sign typically uses a different shape (usually a rectangular shape) and indicates that drivers should prepare to stop. A road closed sign would also not be in a yellow diamond shape and is used to inform about road access restrictions. Speed limit change signs often take on a rectangular shape, displaying the new given speed limit clearly to the drivers. Each of these signs serves a different purpose, but the yellow diamond is specifically meant to warn about potential hazards.