What does a solid white longitudinal line separating traffic lanes moving in the same direction signify to a motorcycle rider?

1. Motorcycles may cross this line freely at any time
2. This line designates a pedestrian-only lane
3. Overtaking and lane changes across the solid line are permitted only during daytime
4. Crossing the solid line to change lanes or overtake is strictly prohibited (禁止跨越同向车道分界线)