What type of signs include "Road Bridge Ahead" and "Animal Crossing Ahead"?

The correct answer identifies these types of signs as "Road Obstacle Signs." This category encompasses signs that warn drivers about potential hazards or obstacles that may require increased caution. "Road Bridge Ahead" informs drivers about an upcoming bridge which may involve particular driving considerations, while "Animal Crossing Ahead" alerts drivers to the possibility of animals crossing the road, which can present unpredictable challenges for safety.

By considering the purpose of these signs, they are meant to convey critical information that helps maintain safety on the roads, prompting drivers to slow down and remain vigilant. In contrast, other categories of signs serve different functions; for instance, road width signs indicate the space available for vehicles, traffic control device signs regulate the flow of traffic through signals or markings, and regulatory signs convey rules that must be followed by road users. Thus, these signs are specifically designed to warn about potential obstacles rather than to regulate behavior or convey structural information.