Which example qualifies as a used vehicle?

A vehicle is classified as "used" when it has been previously owned and has had some form of prior use. In this context, a demo vehicle with 1500 miles qualifies as a used vehicle because it has been driven, albeit as a demonstration model. Even though it may not have been sold to an individual consumer yet, the mileage indicates that it has been in use and is not brand new. It typically signifies that someone has operated the vehicle under normal conditions, which is a key factor in determining its used status.

The other scenarios do not meet the criteria for a used vehicle. An entirely new vehicle has never been owned or operated by anyone other than the dealership and thus is considered new. A vehicle owned for less than one month could still be considered new if it has not been driven or has extremely low mileage, indicating limited use. Lastly, a vehicle that has been registered but never driven is in new condition as it hasn't been used, despite having a registration. Thus, the demo vehicle is the only option that fits the definition of a used vehicle.