Under what conditions is passing on the right allowed?

Passing on the right is permitted in specific situations, primarily when the vehicle ahead is signaling to make a left turn. This is a common scenario in which there is sufficient space to maneuver around the turning vehicle without endangering anyone or violating traffic laws. By allowing such a maneuver, the driver can maintain the flow of traffic and minimize delays.

In contrast, the other options do not accurately represent the circumstances under which passing on the right is legal. For instance, passing on the right is not allowed simply due to the speed limit being over a certain threshold or in all traffic situations. Additionally, while one-way streets can allow passing on the right since traffic generally flows in a single direction, it’s not the only condition under which this action is permissible. The key takeaway is that the primary condition for legally passing on the right focuses on the vehicle ahead's intention to turn left and the space available for safe maneuvering.