When assisting elderly passengers, pregnant women, or passengers with limited mobility who are boarding a city bus, what is the driver's proper civilized practice?

1. Close the door immediately after the passenger steps on the first step and accelerate to keep on schedule
2. Wait patiently until the vulnerable passenger is fully seated or securely holding a safety handrail before closing doors and starting smoothly
3. Honk the horn to urge other seated passengers to leave their seats immediately
4. Instruct the mobility-impaired passenger to board through the rear exit door while the bus is moving