Task: Question Answering
Input (English): Passage: Following the seven performances on the Joshua Tree Tour, U2 did not perform "Mothers of the Disappeared" until 1998, on the fourth leg of the PopMart Tour. It was played at three concerts in Argentina and once in Chile, concluding all four shows. Bono sang "el pueblo vencerá" at the end of each performance. The first rendition was on 5 February 1998 in Buenos Aires, where it was performed with the Madres accompanying them onstage. The song was played by just Bono and the Edge and was set against footage of the Madres on the video screen. At the conclusion of the song, the band members faced the Madres and applauded, an act in which the rest of the audience joined. Part of the performance was later included on the television documentary Classic Albums: The Joshua Tree.The cost of the tickets was too high for many fans in South America, so the band broadcast the 11 February concert in Chile live on television. Knowing that many people in the country would be watching, they played "Mothers of the Disappeared" in place of "Wake Up Dead Man". The stadium in which the concert was held had been used as a prison camp by Pinochet's regime following the coup d'état. Again it was performed solely by Bono and the Edge against footage of the Madres, and they invited the women to join them onstage a second time. The Madres held up photographs of their children and spoke about them briefly during the performance, an act which received a mixed reception from the audience. Bono made a plea to Pinochet, asking him to "tell these women where are the bones of their children.""Mothers of the Disappeared" was performed again on the fourth leg of the Vertigo Tour, on 26 February 2006 in Santiago and 2 March in Buenos Aires. Although it was rehearsed by the full band, it was played only by Bono and the Edge in an arrangement similar to the one from the PopMart Tour. The Edge performed the song on a charango that Chilean President Ricardo Lagos had given to Bono earlier that day. It was played at three concerts on the third leg of the U2 360° Tour in place of "MLK". One performance in Istanbul, Turkey was dedicated to Fehmi Tosun, an ethnic Kurd who was kidnapped in October 1995 and subsequently disappeared. The abduction was witnessed by his wife and daughter; no information regarding his disappearance has ever been released.
For the first time in 30 years, a full band arrangement of "Mothers of the Disappeared" returned to U2's live set for the Joshua Tree Tour 2017, on which the group played The Joshua Tree in sequence in its entirety for each show. Eddie Vedder and Mumford & Sons accompanied U2 on-stage in a performance of the song during a 14 May 2017 show in Seattle. 
Question: What was set against footage of the Madres on the video screen?
Output (English): Mothers of the Disappeared.