What best describes a "non contact unit" in a vehicle collision?

A "non contact unit" in a vehicle collision refers to a vehicle that did not physically participate in the crash. This designation is important for accident analysis as it helps to differentiate between vehicles that were directly involved in the collision and those that may have been affected or present at the scene but were not struck or did not crash into another vehicle. For example, a vehicle that swerved to avoid the collision but was not hit would be considered a non contact unit.

This classification is useful in determining liability and understanding the dynamics of the crash, as it provides a clear picture of the interactions between vehicles during the incident. In contrast, the other choices relate to vehicles that either participated in the crash or were directly impacted, which would not fit the definition of a non contact unit.