Regulatory Signs are often what colors?

Regulatory signs are typically black and white. These signs convey critical instructions and regulations that drivers must follow to ensure safety on the road. The black and white color scheme makes these signs highly visible and easily readable, allowing drivers to quickly understand the required actions or restrictions, such as speed limits, stop signs, and yield signs.

In contrast, other colors mentioned in the options serve different purposes. Red and yellow are often used for warning signs, while green and brown typically indicate directional information or recreational area signs. Yellow and blue are also associated with warning signs and directional information rather than regulatory mandates. Thus, the black and white color scheme uniquely identifies the importance of regulatory signs in traffic management.