What should a driver do if they encounter a school bus with its stop sign extended?

Answer: B — Come to a complete stop

When a driver encounters a school bus with its stop sign extended, the appropriate action is to come to a complete stop. This law is in place to ensure the safety of children boarding or disembarking from the bus. The extended stop sign indicates that children may be crossing the street and that vehicles must halt to provide them a safe passage. Failing to stop could result in severe consequences, including fines and points on the driver's license, as it poses a significant risk to children's safety. It's essential to remain stopped until the stop sign is retracted and the bus begins moving again, ensuring that all children are safely away from the bus and the road. Other options, such as passing the bus or only stopping if children are present, do not prioritize the safety regulations in place for protecting young pedestrians.