What does a double yellow line indicate?

A double yellow line is used to indicate that passing is not allowed in either direction. When you see this marking, it means that the roadway is designed in such a way that attempting to pass could create a dangerous situation, either due to oncoming traffic or other road conditions. This is crucial for maintaining safety on the roads, as it ensures vehicles remain in their respective lanes without overtaking each other in areas where visibility may be limited or where there may be other hazards.

The other options suggest scenarios that contradict the fundamental purpose of the double yellow line. For instance, indicating that passing is allowed on both sides would compromise safety and lead to potential accidents. The notion of only allowing passing from the left also conflicts with the meaning of the double line, as it restricts any passing maneuver altogether. Lastly, stating that no stopping is allowed is incorrect since stopping is determined by various factors such as traffic signals and road signs, not by the presence of double yellow lines.