What type of traffic sign displays regulations that drivers must obey, such as no left turns?

Answer: C — Square Traffic Signs

The correct answer is that rectangular traffic signs display regulations that drivers must obey. These signs are typically used to convey important information regarding rules and laws that must be followed while driving. For instance, a rectangular sign indicating "No Left Turn" clearly informs drivers of the prohibition against making a left turn at that intersection. This shape is specifically designated for regulatory signs, which are critical for maintaining road safety and order. In contrast, diamond-shaped signs are often used for warning purposes to alert drivers to potential hazards ahead, while square signs can indicate service areas or other non-regulatory information. Circular signs are primarily reserved for specific traffic indications, such as railroad crossings or other alerts. Understanding the shapes and their meanings is essential for safe driving and compliance with road regulations.