Task: Question Answering
Input (English): Passage: Casey is an adolescent boy whose life is constantly influenced by his intense fear of clowns. His two older brothers, Geoffrey and Randy, are mostly disobliging. One night, the three boys are left alone when their mother visits relatives, so they decide to visit a local circus for a night of amusement, despite Casey's uncontrollable coulrophobia. Meanwhile, the local state insane asylum has sent a majority of the hospital's inmates to the carnival for therapy, but three psychotic mental patients break away from the group and kill three clowns, taking their makeup and costumes.
While at the circus, Casey innocently visits a fortune teller despite Randy's better judgment. The fortune teller reveals to Casey that his life line has been cut short, and says to him: "Beware, beware, in the darkest of dark /though the flesh is young and the hearts are strong /precious life cannot be long /when darkest death has left its mark."
As the boys return from the circus, a shaken Casey thinks his nightmare is over, but it has only just begun. When the clowns target their home, Casey is forced to face his fears once and for all. Casey and his brothers are locked inside their isolated farmhouse and the power is turned off. Casey attempts to call the police, but because Casey says that the "clowns from the circus are trying to get him", the police officers assume that Casey's fear of clowns caused him to have a realistic nightmare. The officers tell Casey that everything will be fine if he goes back to sleep, and hangs up.
Randy mockingly dresses up as a clown, disbelieving of Casey's claims that clowns are inside the house. His plan to jump out at Geoffrey and Casey is cut short after he is stabbed by one of the clowns. Geoffrey manages to kill the first clown by hitting him with a wooden plank, knocking him down a flight of stairs and breaking his neck. 
Question: Who is disbelieving of someone's claim that clowns are inside the house?
Output (English): Randy.