input question: Generate a question that has the following answer: Yes. for the following movie plot: Susan Selky is a well-known English professor at Columbia University. She lives in a Brooklyn brownstone with her 10-year-old son Alex (Danny Corkill). One March morning, Susan sees Alex off to school, which is only two blocks away. Alex turns to wave to his mother, then disappears around the corner. Susan returns home after work, and becomes increasingly alarmed when Alex is late. She calls her friend and neighbor Jocelyn Norris, whose daughter is a classmate of Alex's, and learns Alex never went to school. She immediately calls the New York City Police Department, and officers descend on the townhouse, led by Lieutenant Al Menetti. Susan is questioned closely on all aspects of her life and her son's, and initially suspect her estranged husband, Graham, a professor at New York University, but he produces an alibi. Susan's case generates attention from the local media, and citizens help in the search by distributing posters. Susan is initially criticized for allowing her son to walk to school by himself. Susan takes a polygraph test that clears her as a suspect. Numerous leads are checked out, including several reports that Alex may have been seen in the back seat of a blue 1965 Chevy. A psychic is also called in, but each lead fizzles. The investigation drags on, and Graham is at odds with Menetti after budget cuts force Menetti to dismantle the command center in Susan's apartment and run the case from the precinct. Menetti's attention is soon diverted to other cases, but the Selky case is always a priority. At one point, Graham takes matters into his own hands after he receives a ransom call. Given a beating, he requires a hospital stay. A break in the case finally happens on the Fourth of July, when Susan's housecleaner, Philippe, is arrested as a suspect. A pair of Alex's bloody underpants was found in his apartment, where the gay Philippe was picked up with a 14-year-old male prostitute. Susan visits Philippe in jail, and he tells her that the bloody underpants came about when he used them to stop...???
output answer: Was Alex kidnapped?

Generate a question that has the following answer: Frank for the following movie plot: The film begins with two recently escaped convicts Frank (James Remar) and Red (Jaimz Woolvett) approach a group of campers. The elder of the pair shoots and kills the campers with single rapidfire shots. D.J. Farraday (Robert Glen Keith) discovers that his father, Del (Stockwell), has been having an affair. D.J. asks Del to meet him at the family's cabin by the lake, where D.J. intends to confront him about his adultery. When the two arrive at the summer house, they find the younger son, Campbell "Cam" Farraday (Behr), already there. Eventually it is revealed that Del had found Cam and his boyfriend, Billy, embracing there at the cabin. Del brutally beat Billy, and father and son have not spoken since. Cam seems determined to leave the confrontational situation. While D.J. is trying to convince Cam to stay and attempt a reconciliation, Cam reveals to him that Billy is dead, and the clear implication is that Cam blames his father for the loss. A short while later, the two escaped convicts show up at the cabin and ask to use the phone, claiming that their car has broken down. Red, who is introduced as Frank's adult son, makes a point of taking up the hospitality offered, using that excuse to remain in the house (over Frank's objection.) As the evening progresses Frank seems to be forcing Del into a challenge. Tensions are high, as Frank makes his play for Alpha of the house. At one point, D.J. (Del Junior) goes so far as to suggest that "we all just whip 'em out and get this over with." The police show up looking for the two escaped convicts, and things get tense very quickly. It soon becomes clear that Cam knew the convicts and has had some sort of entanglement with them. From there, the twists and turns begin to thicken, and the onionskin layers of this tale are revealed. The family must reconcile and put aside their issues with each other to deal with the menacing force of Frank.
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Answer: Who forces Del into a challenge?

Problem: Given the question: Generate a question that has the following answer: party for the following movie plot: As the film opens, Joe Buck (Jon Voight), a young Texan working as a dishwasher, dresses in new cowboy clothing, packs a suitcase, and quits his job. He heads to New York City hoping to succeed as a male prostitute for women. Initially unsuccessful, he succeeds in bedding a well-to-do middle-aged New Yorker (Sylvia Miles), but Joe ends up giving her money. Joe then meets Enrico Salvatore "Ratso" Rizzo (Dustin Hoffman), a street con man with a limp who takes $20 from Joe by offering to introduce him to a known pimp (John McGiver). Joe flees the encounter in pursuit of Ratso. Joe spends his days wandering the city and sitting in his hotel room. Soon broke, he is locked out of his hotel room and most of his belongings are impounded. He tries to make money by agreeing to receive oral sex from a young man (Bob Balaban) in a movie theater. When Joe learns that the young man has no money, Joe threatens him and asks for his watch, but eventually lets him go. The following day, Joe spots Ratso and angrily shakes him down. Ratso offers to share the apartment in which he is squatting in a condemned building. Joe accepts reluctantly, and they begin a "business relationship" as hustlers. As they develop a bond, Ratso's health, which has never been good, grows steadily worse. Joe's story is told through flashbacks. His grandmother raises him after his mother abandons him, and his grandmother abuses him. He also has a tragic relationship with Annie, a local girl. Ratso's backstory comes through stories he tells Joe. His father was an illiterate Italian immigrant shoe-shiner, who worked in a subway station. He developed a bad back, and "coughed his lungs out from breathin' in that wax all day". Ratso learned shining from his father but won't stoop so low as to do so. He dreams of moving one day to Miami. An unusual couple approach Joe and Ratso in a diner and hand Joe a flyer, inviting him to a party. They enter a Warhol-esque party scene (with Warhol superstars in cameos). Joe smokes a joint, thinking it's a normal...
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The answer is:
The flier invites Joe to what?