What does a double yellow line in the center of the road mean?

A double yellow line in the center of the road indicates that no passing is allowed in either direction. This marking is used to enhance roadway safety by clearly signaling to drivers that overtaking or passing other vehicles is prohibited. The presence of this line suggests that conditions are not safe for such maneuvers, which may be due to curves, intersections, or other hazards that could lead to an accident if a driver attempted to pass.

The other options do not accurately reflect the meaning of a double yellow line. For instance, "no stopping allowed" applies to certain zones but is not associated with this type of line. Likewise, indicating that passing is permitted on both sides or that lane changes are allowed with caution contradicts the strict rule intended by double yellow lines. These specific markings serve to promote caution and prevent potentially dangerous driving behaviors on the road.