When installing a rear-facing child safety seat on the front passenger seat, what critical safety step must be performed?

1. The front seat must be pushed as close to the steering wheel as possible
2. The front passenger frontal airbag must be deactivated (çaktivizimi i airbag-ut)
3. The vehicle's hazard warning lights must be left flashing continuously
4. The rear seatbelts must be clipped together into the front buckles