Why is consuming drugs even just once, dangerous for driving on public roads?

Your answer is fully correct because all three points describe important dangers of drug use when driving according to German traffic rules. Consuming drugs even once can make you unfit to drive (point 1) because they affect your physical and mental abilities. Drugs can cause intoxication that lasts for several hours (point 2), meaning you might still be impaired long after consumption. Also, drugs can cause faulty perceptions (point 3), such as distorted vision, slower reaction times, or impaired judgment, which significantly increase the risk of accidents. Understanding these effects helps explain why drug use is prohibited and strictly controlled for drivers to ensure road safety.