Information:  - The Beatles were an English rock band, formed in Liverpool in 1960. With members John Lennon, Paul McCartney, George Harrison and Ringo Starr, they became widely regarded as the foremost and most influential act of the rock era. Rooted in skiffle, beat, and 1950s rock and roll, the Beatles later experimented with several musical styles, ranging from pop ballads and Indian music to psychedelia and hard rock, often incorporating classical elements and unconventional recording techniques in innovative ways. In the early 1960s, their enormous popularity first emerged as "Beatlemania", but as the group's music grew in sophistication, led by primary songwriters Lennon and McCartney, they came to be perceived as an embodiment of the ideals shared by the counterculture of the 1960s.  - Sir George Henry Martin (3 January 19268 March 2016) was an English record producer, arranger, composer, conductor, audio engineer and musician. He was referred to as the "Fifth Beatle", including by Paul McCartney, in reference to his extensive involvement on each of the Beatles' original albums. Martin had 30 number-one hit singles in the United Kingdom and 23 number-one hits in the United States.  - Brian Samuel Epstein (19 September 1934 27 August 1967) was an English music entrepreneur, best known for managing the Beatles. Epstein first discovered the Beatles in November 1961 during a lunchtime Cavern Club performance. He was instantly impressed and saw great potential in the group. Epstein was rejected by nearly all major recording companies in London, until he secured a meeting with George Martin, head of EMI's Parlophone label. In May 1962, Martin agreed to sign the Beatles, partly because of Epstein's conviction that the group would become internationally famous.  - Ferry Cross the Mersey is a 1965 musical film featuring Gerry and the Pacemakers . The film , directed by Jeremy Summers , is one of the more uncommon artifacts of the Mersey scene , shown very rarely on television and never issued on video . It was the first to be shot on location in Liverpool after the city 's emergence into the music mainstream ( which had previously seen only Frankie Vaughan , Russ Hamilton , and Billy Fury as stars ) . For authenticity , many scenes were shot in clubs near the home of Gerry and the Pacemakers ' frontman Gerry Marsden . A scene on a ferry ( the Mountwood ) on the River Mersey showed the docks as a backdrop . Marsden wrote nine new songs for the film which also starred Julie Samuel , Cilla Black singing `` Is it Love ? '' , Jimmy Savile , and The Fourmost . Future Doctor Who actress Elisabeth Sladen appeared in the film as an uncredited extra . The song `` Ferry Cross the Mersey '' was written by Gerry Marsden as the theme song for the film . As of March 2014 , the film has never seen a commercial release . Neil Aspinall owned the rights to the movie in the past before his death . For the soundtrack , see Ferry Cross the Mersey .  - Gerry and the Pacemakers were an English beat group prominent in the 1960s Merseybeat scene. In common with the Beatles, they came from Liverpool, were managed by Brian Epstein, and were recorded by George Martin.     After reading the paragraphs above, we are interested in knowing the entity with which 'ferry cross the mersey ' exhibits the relationship of 'producer'. Find the answer from the choices below.  Choices: - brian epstein  - george harrison  - george martin  - ringo starr  - the beatles
brian epstein