Question: When ELO's Greatest Hits was released, who was the band leader of the Electric Light Orchestra (ELO)?

Context paragraphs:
A New World Record: A New World Record is the sixth studio album by Electric Light Orchestra (ELO).  It was released on 11 September 1976 in the United Kingdom by Jet Records, and a day later in the United States by United Artists Records.  "A New World Record" marked ELO's shift towards shorter pop songs, a trend which would continue across their career.  Their second album to be recorded at Musicland Studios in Munich, the LP proved to be the band's breakthrough in the UK; after their previous three studio recordings failed to chart in their home market, "A New World Record" became their first top ten album in the UK.  It became a global success and reached multi-platinum status in the US and UK, The album sold five million units worldwide within its first year of release.  The cover art features the ELO logo, designed by Kosh, for the first time.  This logo would be included on most of the group's subsequent releases.  The album yielded four hit singles, including "Livin' Thing", the transatlantic Top Ten hit "Telephone Line", which became the band's first gold US single, the UK Top Ten hit "Rockaria! ", and the US number 24 hit "Do Ya", a remake of the 1972 single by The Move, of which Lynne was a member between 1970 and 1972.

Alone in the Universe: Alone in the Universe is the thirteenth studio album by British rock band Electric Light Orchestra (ELO), and the first credited to Jeff Lynne's ELO.  The moniker came out from Lynne as a response to ELO tribute and imitation bands, who repeatedly used ELO for promoting their own tours.  Released on 13 November 2015, the album is the first of new original material credited to the group since "Zoom" in 2001, and the second since the original group's disbandment in 1986.  The album was met with generally favourable reviews, peaking at number two on the "Billboard" Top Rock Albums and number four on the UK Albums Chart, where it has been certified Platinum.

ELO 2: ELO 2 is the eponymous second studio album by the Electric Light Orchestra (ELO), released in 1973.  In the US, the album was released as Electric Light Orchestra II.  It was also the last album to be released by the band under the Harvest label, the last where the band used the definite article "The" on its name and introduced their acronym ELO.

Richard Tandy: Richard Tandy (born 26 March 1948) is an English musician, best known as the keyboardist in the rock band Electric Light Orchestra ("ELO").  His palette of keyboards (including Minimoog, Clavinet, Mellotron, and piano) was an important ingredient in the group's sound, notably on the albums "A New World Record", "Out of the Blue", "Discovery", and "Time".  Tandy was inducted into the Rock and Roll Hall of Fame on 7 April 2017 as a member of Electric Light Orchestra.

Secret Messages: Secret Messages is the tenth studio album by Electric Light Orchestra (ELO), released in 1983 through Jet Records.  It was the last ELO album with bass guitarist Kelly Groucutt, conductor Louis Clark, and real stringed instruments, and the last ELO album to be released on Jet Records.  It was also the final ELO studio album to become a worldwide top 40 hit upon release.

The Essential Electric Light Orchestra: The Essential Electric Light Orchestra is a single CD, US-only compilation album by the Electric Light Orchestra (ELO), released in 2003.  It is part of Sony Music's "The Essential" series.  It was preceded by US compilations "Olé ELO" in 1976 and "" in 1995.

Electric Light Orchestra: The Electric Light Orchestra (ELO) are an English rock band formed in Birmingham in 1970, by songwriters/multi-instrumentalists Jeff Lynne and Roy Wood with drummer Bev Bevan.  Their music is characterised by a fusion of Beatlesque pop, classical arrangements, and futuristic iconography.  After Wood's departure in 1972, Lynne became the band's leader, arranging and producing every album while writing virtually all of their original material.

ELO's Greatest Hits Vol. 2: ELO's Greatest Hits Vol.  2 is an album by the Electric Light Orchestra (ELO), released in 1992 as a follow up to their more successful "ELO's Greatest Hits" (Not issued in the U.S.).

The Electric Light Orchestra (album): The Electric Light Orchestra is the eponymous debut studio album by English rock band Electric Light Orchestra (ELO), released in December 1971 in the United Kingdom by Harvest Records.  In the United States, the album was released in early 1972 as No Answer, after a misunderstood telephone message made by a United Artists Records executive asking about the album name; the caller, having failed to reach the ELO contact, wrote down "no answer" in his notes, and this was misconstrued to be the name of the album.

ELO's Greatest Hits: ELO's Greatest Hits is a compilation by the Electric Light Orchestra (ELO), released in 1979.

Supporting paragraphs: ELO's Greatest Hits Electric Light Orchestra
Answer: Jeff Lynne