What does a double solid yellow line indicate?

A double solid yellow line indicates that no passing is allowed in either direction. This is a critical traffic rule designed to ensure safety on roadways where visibility may be limited or where it is deemed unsafe to pass other vehicles. The presence of the double solid yellow lines signals to drivers that crossing these lines is prohibited, thereby minimizing the risk of collisions by clearly demarcating areas where passing could be dangerous. Understanding this sign is essential for maintaining safe driving practices and ensuring compliance with traffic regulations.

The other choices suggest actions that are permissible, which contradicts the clear intent of the double solid yellow line. For instance, the notion of allowing passing after sundown or permitting lane changes does not align with the primary function of these lines, which is to restrict such movements for safety reasons.