Which line pattern allows you to switch lanes where safe?

Answer: C — A dashed white line between lanes indicates you must stop.

Line patterns tell you when lane changes are allowed. The dashed white line between lanes moving in the same direction lets you switch lanes or pass, but only when it’s safe. Before crossing, signal, check your mirrors and blind spots, and ensure there’s enough space and no oncoming or neighboring-traffic danger. A solid yellow line means no passing on your side, so crossing to pass isn’t allowed. A dashed white line does not indicate stopping, and a solid white line marks a lane boundary you should not cross except for entering or exiting a roadway or making a turn. So, the line pattern that allows switching lanes safely is the dashed white line between lanes moving in the same direction.