Question:  "On My Mind" is a song by English singer Ellie Goulding that many critics considered an answer to a song recorded by what English singer-songwriter for his second studio album?
Context: "On My Mind" is a song by English singer Ellie Goulding from her third studio album "Delirium" (2015).  It was released as the album's lead single on 17 September 2015.  It was written by Goulding, Max Martin, Savan Kotecha and Ilya Salmanzadeh.  "On My Mind" is an electropop and R&B song whose instrumentation consists of scratchy guitars, trap drums, slapped beats and sharp, syncopated electronica.  Lyrically, "On My Mind" talks about a one-night stand with someone the protagonist shouldn't be with, having a dichotomy between heart and head.  Though firmly denied by Goulding, many critics considered it an answer song to Ed Sheeran's "Don't". "Outside" is a song by Scottish DJ and record producer Calvin Harris from his fourth studio album, "Motion" (2014).  The song features English singer Ellie Goulding and was released on 20 October 2014 as the fourth single from the album.  It marks the second collaboration between Harris and Goulding, following the single "I Need Your Love" (2013).  "Outside" is also included on the deluxe edition of Goulding's third studio album, "Delirium". Halcyon Days is the reissue of English singer Ellie Goulding's second studio album, "Halcyon" (2012).  It was released on 23 August 2013 by Polydor Records.  Following the release of "Halcyon", Goulding announced that she had plans to repackage the original album, with new songs that focused on electronic music.  For the reissue, Goulding recorded 10 new songs and worked with a variety of producers, including Ryan Tedder, Calvin Harris and Greg Kurstin, to create her desired sound. "Flashlight" is a song by English singer and songwriter Ellie Goulding featuring production work from DJ Fresh, released as the fourth single from Fresh's forthcoming fourth studio album.  It was released on 28 September 2014 in the United Kingdom as a single, although it was previously out on Goulding's album from 2013.  The song features English singer and songwriter Ellie Goulding and also included as one of the tracks on Goulding's "Halcyon Days" (2013), the reissue of her second studio album, "Halcyon" (2012).  The Invisible Men assisted the artists in writing the song. "Love Me like You Do" is a song recorded by English singer Ellie Goulding for the "Fifty Shades of Grey" (2015).  The song was written by Savan Kotecha, Ilya Salmanzadeh, Tove Lo, Max Martin and Ali Payami; the latter two also produced it.  Goulding was selected to sing the track.  It was released on 7 January 2015 as the second single from the soundtrack.  The song was also included on Goulding's third studio album, "Delirium" (2015). An Introduction to Ellie Goulding is the debut extended play (EP) by English singer Ellie Goulding, released on 20 December 2009 by Polydor Records.  The EP was released shortly after Goulding was nominated for the BBC Sound of 2010, which she ultimately won. "Don't" is a song recorded by English singer-songwriter, Ed Sheeran, for his second studio album, "×" (2014).  Written by Sheeran and Benny Blanco and produced by Blanco and Rick Rubin, the song samples "Don't Mess with My Man" by Lucy Pearl.  It was initially planned as the album's lead single, but was passed over in favour of "Sing".  It was instead released to iTunes on 13 June 2014 as the second "instant grat" promotional single from "×".  "Don't" officially impacted US contemporary hit radio on 15 July 2014 and was released independently on 24 August 2014 as the album's second single. "I Need Your Love" is a song by Scottish producer and DJ Calvin Harris from his third studio album, "18 Months" (2012).  The song features English singer Ellie Goulding and was released on 12 April 2013 as the album's seventh single.  "I Need Your Love" is also included as a bonus track on Goulding's second studio album, "Halcyon" (2012).  The accompanying music video, directed by Emil Nava, depicts Harris and Goulding as a romantic couple on a trip to Miami. "Burn" is a song by English singer Ellie Goulding from "Halcyon Days" (2013), the reissue of her second studio album, "Halcyon" (2012).  The song was written by Ryan Tedder, Goulding, Greg Kurstin, Noel Zancanella and Brent Kutzle, while production was handled by Kurstin and vocal production was done by Tedder.  It was released on 5 July 2013 as the lead single from the reissue.  The song was originally recorded by singer Leona Lewis for her third studio album, "Glassheart" (2012), but it was ultimately scrapped. "Heavy Crown" is a song recorded by Australian rapper Iggy Azalea featuring English singer Ellie Goulding, recorded for "Reclassified" (2014), the reissue of Azalea's debut studio album "The New Classic" (2014).  Azalea and Goulding co-wrote the song with its producers, Salt Wives and The Invisible Men, with additional writing from Jon Turner.  "Heavy Crown" received generally positive reviews from critics, who commended Azalea's delivery on the track, finding it to be superior to that of her earlier songs.
Answer: Ed Sheeran