What does a solid double yellow line indicate?

A solid double yellow line indicates that no passing is allowed in either direction. This clear marking is used to enhance safety on roads where visibility may be limited or where there are other hazards that make passing dangerous. The presence of double solid lines serves as a warning to drivers to remain in their lane and not attempt to overtake another vehicle.

This regulation is important for maintaining traffic flow and reducing the risk of collisions, especially in areas with high traffic volume or complex road conditions. The other options suggest scenarios that do not align with the established traffic laws governing road markings.