Answer:
The most effective approach to dealing with foreigners who sell drugs would be to strengthen law enforcement and border control efforts. This includes working with other countries to cooperate on information sharing and extradition. Additionally, rehabilitation and education programs should be implemented to address the root causes of drug abuse and addiction within the local community. Harsh penalties could also be implemented for drug dealers and traffickers. Ultimately, a combination of these approaches could help to reduce the influx of drugs into the community and address the issue of drug abuse.