Which of the following is classified as a prohibited firearm?

A fully automatic firearm is classified as a prohibited firearm because it is designed to fire continuously with a single pull of the trigger. This capability poses significant safety and security risks, leading many jurisdictions to impose strict regulations or outright bans on their possession and use. These kinds of firearms are often associated with military or police use, rather than civilian applications, and their regulation aims to prevent misuse in criminal activities and to ensure public safety.

In contrast, tranquilizer firearms, paintball guns, and air guns do not fall into the same category of prohibited firearms. Tranquilizer firearms are typically used in veterinary medicine or animal control, while paintball guns are designed for sport and recreational purposes. Air guns, which use compressed air to propel projectiles, are generally subject to different regulations and are often seen as less dangerous than fully automatic firearms.