A driver on a one-lane-per-direction urban street is travelling at 30 km/h. A sign ahead sets 20 km/h on a shared-platform section. What applies in the shared section?

1. 30 km/h because it is the default for one lane each direction
2. 20 km/h because the specific sign and shared-platform rule are lower
3. 50 km/h because it is still urban
4. The driver may choose any speed below 90 km/h