Answer:
True. 18-year old teenagers that practice some sport or have a hobby have less references to substance abuse or violence.
Explanation:
When someone practices a certain sport, he/she is occupied with its sport, also, sports encourage responsability, discipline and takes most of the person´s time and energy. People who doesn´t practice sports or have any hobby have more idle time and is always looking for something to take away the boredom. Most of the cases they start doing drugs or start having violent episodes because is what´s more handful and gives them the dopamine that the sport is not giving them (because they don´t practice any).
This is way the display of sports or hobbies involvements is associated with decreased references to risky behavior.