Final answer:
You should slow down and proceed with caution when road signs indicate higher-than-normal hazardous conditions, such as near school zones or construction areas.
Step-by-step explanation:
You should slow down and proceed with caution when road signs indicate there are higher-than-normal hazardous conditions. An example could be when a sign is posted near a school zone, construction area, or a sharp curve, specifically instructing drivers to be more cautious than usual under these circumstances. The correct answer is not to always slow down regardless of conditions, nor to do so only during rush hour; instead, you should heed the specific signs designed to enhance safety in potentially dangerous driving conditions.