welcome back to "cnn newsroom," i'm george howell. hillary clinton main republican rival is face something problems of his own right now. donald trump stumbled on a foreign policy question with a conservative radio host and he calls it a gotcha question. the presidential candidate fumbled when asked if he recognized the names of leaders of isis and other islamic militant groups. he also said he misheard a question from radio host hugh hewitt about the head of iran's elite qods forces. >> are you familiar with general soleimani. >> yes. >> he runs the qods forces. >> right. i think the kurds by the way have been horribly mistreated by -- >> not the kurds, the qods