You will be given a definition of a task first, then some input of the task.
In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.

Passage: The band faced several challenges in writing their second album, October. On an otherwise successful American leg of the Boy Tour, Bono's briefcase containing in-progress lyrics and musical ideas was lost backstage during a March 1981 performance at a nightclub in Portland, Oregon. The band had limited time to write new music on tour and in July began a two-month recording session at Windmill Lane Studios largely unprepared, forcing Bono to quickly improvise lyrics. Lillywhite, reprising his role as producer, called the sessions "completely chaotic and mad". October's lead single, "Fire", was released in July and was U2's first song to chart in the UK. Despite garnering the band an appearance on UK television programme Top of the Pops, the single fell in the charts afterwards. On 16 August 1981, the group opened for Thin Lizzy at the inaugural Slane Concert, but the Edge called it "one of the worst shows [U2] ever played in [their] lives". Adding to this period of self-doubt, Bono's, the Edge's, and Mullen's involvement in a Charismatic Christian group in Dublin called the "Shalom Fellowship" led them to question the relationship between their religious faith and the lifestyle of a rock band. Bono and the Edge considered quitting U2 due to their perceived spiritual conflicts before deciding to leave Shalom instead.October was released in October 1981 and contained overtly spiritual themes. The album received mixed reviews and limited radio play, and although it debuted at number 11 in the UK, it sold poorly elsewhere. The single "Gloria" was U2's first song to have its music video played on MTV, generating excitement for the band during the October Tour of 1981–1982 in markets where the television channel was available. During the tour, U2 met Dutch photographer Anton Corbijn, who became their principal photographer and has had a major influence on their vision and public image. In March 1982, the band played 14 dates as the opening act for the J. Geils Band, increasing their exposure. Still, U2 were disappointed by their lack of progress by the end of the October Tour. Having run out of money and feeling unsupported by their record label, the group committed to improving; Clayton recalled that "there was a firm resolve to come out of the box fighting with the next record".
Output:
What band appeared on Top of the Pops?