Under ZOBS BiH, what is required if a commercial truck driver cannot obtain a clear, complete view of the rear area while reversing?

1. The driver must engage a qualified person (spotter / pomagač) outside the vehicle to guide the reversing maneuver safely
2. The driver must accelerate in reverse while sounding the horn continuously
3. The driver may reverse blindly if hazard lights are active
4. Reversing is completely prohibited under all circumstances throughout the country