According to Article 62 of the Regulations for the Implementation of the Road Traffic Safety Law of the PRC, which of the following rules strictly applies to passenger vehicle doors during transit?

1. Doors may remain slightly ajar on hot summer days if the air conditioning is insufficient
2. Vehicles must not be moved or driven if passenger doors are not completely closed (车门未关好不准起步)
3. Rear exit doors may be opened in advance while gliding into a bus stop to speed up passenger turnaround
4. The driver may allow passengers to push open pneumatic doors while slowing down at red traffic lights