A sign with this shape means:

No passing zone.
Right turn permitted on red.
Yield right-of-way.
The Correct Answer and Explanation is :
The correct answer is: No passing zone.
Explanation:
The sign in the image is a regulatory traffic sign, specifically indicating a no passing zone. This type of sign is essential for maintaining safety on the road and preventing accidents. It is commonly used to inform drivers that they are not allowed to overtake other vehicles within that section of the road, either due to visibility restrictions or the potential for unsafe conditions.
No passing zones are typically marked at locations where it is difficult for drivers to see oncoming traffic, such as on hills, curves, intersections, or narrow roads. These areas are chosen based on a variety of factors including road geometry, visibility, and traffic density. The purpose of this sign is to reduce the risk of head-on collisions, which are more likely when drivers attempt to pass another vehicle without clear visibility of the road ahead.
The sign shown in the image is specifically a pennant-shaped sign, which is used universally in the United States to denote a no passing zone. The shape and color of the sign help drivers quickly identify and react to the warning. The shape is designed to be highly visible, particularly when approaching from the side, ensuring that drivers can see it well in advance and prepare to adhere to the rule.
Understanding and obeying such signs is crucial for safe driving. Passing in a no-passing zone can lead to serious consequences, including fines, license points, and, more importantly, severe accidents. This rule is especially vital for drivers who may not be familiar with the road conditions and who might otherwise attempt to overtake without recognizing the potential danger.
In summary, the no passing zone sign communicates that overtaking other vehicles is prohibited in that specific section of the road due to safety concerns, ensuring that traffic flow remains controlled and collisions are minimized.