Question: What singer made a guest appearance on the single which was eventually included in the greatest hits album released in 1988 by Dire Straits?
Context: The Best of ABBA is a compilation greatest hits album by Swedish pop group ABBA, released in November 1975 in Australia, Germany, the Netherlands, New Zealand and Norway, and in 1976 in Austria and India.  Globally ABBA released "Greatest Hits".  The album topped the charts in Australia, Austria and New Zealand, and went on to be certified 24x Platinum in New Zealand and 22x Platinum in Australia.  The album is tied with Dire Straits' album "Brothers in Arms" for being the best-selling album in New Zealand. Sultans of Swing: The Very Best of Dire Straits is the second greatest hits compilation by the British rock band Dire Straits, released on 19 October 1998 by Mercury Records internationally, and by Warner Bros.  Records in the United States.  The album was originally released, featuring liner notes by Robert Sandall, as both a one-disc edition and two-disc edition.  The second disc contains live performances.  The release is named after the band's 1978 hit single of the same name.  The compilation was re-released together with a DVD in 2002.  The DVD features the music videos of all the songs on the first disc, in addition to short interviews with Mark Knopfler about each song. "Water of Love" is a song written by Mark Knopfler and originally released on Dire Straits' self-titled debut album.  It was also released as a single in some countries, backed by "Down to the Waterline," as a follow-up to the band's first single from the album, "Sultans of Swing."  The single reached #28 on the Dutch charts.  It also reached #54 in Australia.  The song was also included on Dire Straits live album "Live at the BBC" and on the multi-artist compilation album "More Than Unplugged". "Money for Nothing" is a single by British rock band Dire Straits, taken from their 1985 studio album "Brothers in Arms".  The song's lyrics, considered controversial at the time of the song's release, are written from the point of view of a working-class man watching music videos and commenting on what he sees.  The song features a guest appearance by Sting singing background vocals, providing both the signature falsetto introduction and backing chorus of, "I want my MTV."  The groundbreaking video was the first to be aired on MTV Europe when the network launched on 1 August 1987. The Dire Straits Tour was the first concert tour by the British rock band Dire Straits.  The tour started on 9 June 1978 and included 55 concerts throughout Europe, ending on 18 November 1978.  The tour promoted and supported the release of the band's debut album, "Dire Straits", which was released on 7 October 1978.  The tour setlist consisted mainly of songs from their debut album. Money for Nothing is a greatest hits album by British rock band Dire Straits released on 17 October 1988.  It features highlights from the band's first five albums.  The vinyl edition omits "Telegraph Road" and has a different running order, with "Tunnel of Love" placed between "Money for Nothing", the title track, and "Brothers in Arms".  The collection went to #1 on the UK Albums Chart.  It sold 14 million copies worldwide, malking it one of the biggest selling compilation of all time. Dire Straits is the debut studio album by the British rock band Dire Straits released on 7 October 1978 by Vertigo Records internationally and by Warner Bros.  Records in the United States.  The album produced the hit single "Sultans of Swing", which reached #4 on the "Billboard" Hot 100 chart and number 8 on the UK Singles Chart.  The album reached #1 on album charts in Germany, Australia and France, #2 in the United States and #5 in the United Kingdom.  "Dire Straits" was later certified double-platinum in both the United States and the United Kingdom. Greatest Hits is the second greatest hits album and final release by Irish boy band Westlife.  It was released on 18 November 2011 by RCA Records and Sony Music.  "Greatest Hits" is the group's second greatest hits album following "" (2002).  The album is the group's first album not under Syco Music and not under the tutelage of Simon Cowell, having left Syco and Cowell in March 2011.  The greatest hits album contains numerous singles that span throughout the band's career, as well as four new songs produced by John Shanks, which includes the lead single "Lighthouse", which was released on 14 November 2011.  The compilation was released in two different formats, a standard edition containing the album's eighteen tracks, and a deluxe edition featuring numerous other singles of the band's discography, as well as a DVD containing almost all of the band's music videos. Private Investigations: The Best of Dire Straits & Mark Knopfler is the third compilation album by Dire Straits and British singer-songwriter and guitarist Mark Knopfler, released in 2005 by Mercury and Vertigo internationally, and Warner Bros. in the United States.  Named after their 1982 hit single, the album consists of material by Dire Straits, with songs selected from the group's six studio albums (excluding the 1979 album "Communiqué") from 1978 up through the group's dissolution in 1995.  It also features work from the solo career of the group's singer, songwriter, and guitarist Mark Knopfler, including some of his soundtrack material. Dance Again... the Hits is the first greatest hits album of American singer Jennifer Lopez.  It was released on July 20, 2012, by Epic Records, to coincide with the launch of her first world tour, the Dance Again World Tour.  Lopez previously conceived plans for a greatest hits album in 2009, but instead opted to use the material recorded for her seventh studio album, "Love? ", which was released by Island Records in May 2011 after her departure from Epic Records in 2010.  As Lopez owed the label one last album to fulfill her contract, she began work on a new greatest hits album in November 2011.  She later became unsure whether she wanted to go along with plans to release a greatest hits album or a new studio album, eventually deciding on the former.
Answer: Sting