Which of the vehicledrivers parked incorrectly to disembark passengers?

Explanation

Stopping is barred on a pedestrian crossing and within its protected approach-side zone. The motorcycle is on the crossing and the bus is within that approach zone, while the sedan is beyond the crossing in the direction of travel. If travel ran the other way, the violating pair would be the sedan and motorcycle, but that combination is absent from the answer set; the available combination of motorcycle and bus therefore matches the vehicles' positions.