During the Spring Festival, the sale of counterfeit train tickets has become a major public nuisance. The public security department has carried out a number of raids on this, smashed a group of dens that manufacture and sell counterfeit train tickets, and arrested and punished a group of them for profit, However, the phenomenon of trafficking in counterfeit train tickets in society still exists. If the above conclusion is true, which of the following cannot be the reason why the phenomenon of selling fake train tickets still exists? ["The buyer's market for fake train tickets still exists.", 'Only a small percentage of the fake dens found were found.', 'Train tickets lack effective anti-counterfeiting marks.', 'The railway transportation department is still selling station tickets.']