Context: The band, now revitalised by the response to Live Aid – a "shot in the arm" Roger Taylor called it, — and the ensuing increase in record sales, ended 1985 by releasing the single "One Vision", which was the third time after "Stone Cold Crazy" and "Under Pressure (with David Bowie)" that all four bandmembers received a writing credit for the one song. Also, a limited-edition boxed set containing all Queen albums to date was released under the title of The Complete Works. The package included previously unreleased material, most notably Queen's non-album single of Christmas 1984, titled "Thank God It's Christmas".

Question: How many band members wrote Queen's One Vision?

Answer: four