If a visually impaired commuter boards the bus with a trained guide dog, what should the driver do?

1. Refuse entry because animals are strictly prohibited on public transport
2. Allow the passenger and the guide dog to board, ensuring the dog is under control, and do not charge an extra fare
3. Instruct the passenger to place the dog in a closed pet carrier bag
4. Make the passenger sit at the very back of the bus to avoid complaints