A - Alarm
Alarm - The two basic types of car alarm are perimetric and volumetric. The former protects the car's perimeter while the latter protects the interior. In many cases, when the two are combined, you can turn off the volumetric protection to allow a person or animal to stay in the car for a short time, even though the alarm has been set. The most advanced systems incorporate a motion sensor, which guards against the car being towed away.
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