A policeman may stop a vehicle and have it checked:

1. After the vehicle involuntarily swerved from its lane.
2. Correct answer: Due to the level of pollution emitted from the vehicle’s engine.
3. If he wants to esure that the vehicle’s oil consumption corresponds to the vehicle manufacturer’s manual.
4. If he wants to ensure that the vehicle’s fuel consumption corresponds to the vehicle manufacturer’s manual.

WhyA police officer may stop a vehicle for a check if it pollutes the air more than allowed. Fuel or oil consumption is no reason.