The album also featured the hit single "Bohemian Rhapsody", which was number one in the UK for nine weeks. Mercury's close friend and advisor, Capital London radio DJ Kenny Everett, played a pivotal role in giving the single exposure. It is the third-best-selling single of all time in the UK, surpassed only by Band Aid's "Do They Know It's Christmas?" and Elton John's "Candle in the Wind 1997", and is the best-selling commercial single in the UK. It also reached number nine in the United States (a 1992 re-release reached number two on the Billboard Hot 100 for five weeks). It is the only single ever to sell a million copies on two separate occasions, and became the Christmas number one twice in the UK, the only single ever to do so. "Bohemian Rhapsody" has been voted numerous times the greatest song of all time. The band decided to make a video to help go with the single and hired Trilion, a subsidiary of the former management company Trident Studios, using new technology to create the video; the result is generally considered to have been the first "true" music video ever produced, and popularised the medium. The album's first track "Death on Two Legs" is said to be written by Mercury about Norman Sheffield and the former management at Trident who helped make the video so popular. Although other bands, including the Beatles, had made short promotional films or videos of songs prior to this, generally, those were specifically made to be aired on specific television shows. On the impact of "Bohemian Rhapsody", Rolling Stone states: "Its influence cannot be overstated, practically inventing the music video seven years before MTV went on the air." The second single from the album, "You're My Best Friend", the second song composed by John Deacon, and his first single, peaked at number sixteen in the United States and went on to become a worldwide Top Ten hit. The band's A Night at the Opera Tour began in November 1975, and covered Europe, the United States, Japan, and Australia.

Which Queen song was number one on the UK charts for nine weeks?