What does a rectangular construction sign often indicate?

A rectangular construction sign is typically used to provide regulatory information related to specific rules that apply in a construction zone. These signs are essential for ensuring the safety of both drivers and workers on roadways where construction activities are taking place. They often convey important guidelines or restrictions, such as speed limits, lane use, and other regulations that must be followed to maintain safety.

For instance, you might see a rectangular sign indicating a reduced speed limit because of ongoing construction, which advises drivers to slow down and stay alert while navigating through the area. The clear, straightforward design of these signs ensures that the information is easily understood by motorists.

While the other answer choices address aspects of road safety and construction, they pertain to different types of signs or functions. For example, warnings of upcoming hazards often use diamond-shaped signs, while traffic route changes may be indicated with various shapes to emphasize detours or reroutes. Directions for detours can be communicated through various signage styles, often more specific and directive than regulatory information.