What color and shape is a Wrong Way sign?

A Wrong Way sign is designed to alert drivers that they are about to enter a road or area where they should not be, typically a one-way street in the opposite direction. The sign's color and shape play a crucial role in conveying this urgent message.

The use of a red rectangle with white letters is significant because red is universally associated with alerts and potential danger, effectively catching the driver's attention. The rectangular shape helps to standardize traffic signage for easy recognition, ensuring that drivers quickly understand the nature of the warning. This combination of colors and shapes is vital for the effective communication of critical information to help prevent accidents.

In contrast, the other options represent different types of signs that convey various messages but not specifically "Wrong Way." For instance, a green circle typically indicates permitted actions, a yellow diamond warns of caution, and a blue square provides information on services—none of which serve as a specific directive against entering a wrong-way situation.