Final answer:
The yellow pennant-shaped sign indicates a no passing zone, which advises against overtaking other vehicles due to potential oncoming traffic hazards.
Step-by-step explanation:
The question asks about the meaning of a yellow pennant-shaped road sign, specifically inquiring among four choices which include No parking, No U-turn, School zone, and Merge left. The correct interpretation of this sign is that it indicates a no passing zone. This type of sign is used to warn drivers that they should not overtake other vehicles because of potentially dangerous conditions, such as a curving road where visibility of oncoming traffic is limited or nonexistent.
Pennant-shaped traffic signs are less common than other shapes, hence they can bring confusion, but remembering their distinct shape is aligned with increased caution can be helpful in retaining their meaning.
School zones and the activities associated with them, like pedestrian safety, are typically marked with distinct signage featuring, for example, the silhouette of a pedestrian or a child, often accompanied by relevant speed limit information. Meanwhile, merge signs are generally rectangular with additional text or arrows indicating the direction of the merge.