Question: Brian Christopher Kay, is an English radio presenter, conductor and singer, and he was the lowest frog in We All Stand Together, a song by who?

Context paragraphs:
David Lloyd (broadcaster): David Lloyd is an English radio presenter and a former radio executive,

Gary King (radio): Gary King (born 4 August 1963) is an English radio presenter, who has worked for Magic 105.4 Capital FM, BBC Radio 1 and Jazz FM (UK).  He was the first presenter on Atlantic 252, launching the station on 1 September 1989.

Alan Robson: Alan Robson MBE (born 1 October 1955) is an English radio presenter who hosts "Alan Robson's Night Owls" a widely listened to talk show on Metro Radio and TFM Radio in North East England.  He claims that in November 2000 he received a Masters in Exoricsm and Spiritualism at Birkbeck, University of London.

Simon Mayo: Simon Andrew Hicks Mayo (born 21 September 1958) is an English radio presenter who has worked for BBC Radio since 1981.  Mayo is the presenter of "Simon Mayo Drivetime" on BBC Radio 2 which he has done since 2010 and with Mark Kermode, presenter of "Kermode and Mayo's Film Review" on BBC Radio 5 Live.

We All Stand Together: "We All Stand Together" (sometimes referred to as the Frog Song or the Frog Chorus) is a song by Paul McCartney and the Frog Chorus.

Mark Page: Mark Page (born in Middlesbrough) is an English radio presenter and announcer.  Between 1983 and 1986 he was the presenter of the BBC Radio 1 early weekend breakfast show.

Andy Archer (radio presenter): Andy Archer (born Anthony Andrew Dawson) is an English radio presenter, best known for his work on pirate radio stations in the United Kingdom in the 1960s and 1970s.  He later worked for Independent Local Radio and BBC Local Radio.

Jo Russell: Jo Russell is an English radio presenter, currently working for Free Radio and Gem 106.

Brian Kay: Brian Christopher Kay (born 12 May 1944) is an English radio presenter, conductor and singer.  He is well known as the bass in the King's Singers during the group's formative years from 1968 until 1982, and as such is to be heard on many of their 1970s LP recordings.  He was also the voice of Papageno in the film "Amadeus" and the lowest frog in the Paul McCartney song "We All Stand Together" (The Frog's Chorus).

Rupert and the Frog Song: Rupert and the Frog Song is a 1984 animated film based on the comic strip character Rupert Bear, written and produced by Paul McCartney and directed by Geoff Dunbar.  The making of "Rupert and the Frog Song" began in 1981 and ended in 1983.  The film was released theatrically as an accompaniment to McCartney's feature film "Give My Regards to Broad Street".  The song "We All Stand Together" from the film's soundtrack reached No. 3 when released in the UK Singles Chart.  It was released in 2004 as one of the segments of "".

Supporting paragraphs: Brian Kay We All Stand Together
Answer: Paul McCartney