In 1975, Elton John reached No 1 with a cover of which Beatles song? Correct
In a remarkable fusion of two rock dynasties, Elton John dominated the Billboard Hot 100 in early 1975 with his vibrant rendition of the Beatles’ psychedelic masterpiece, “Lucy in the Sky with Diamonds.” This specific version was recorded at the legendary Caribou Ranch in Colorado and featured a very special guest: John Lennon himself, who provided backing vocals and guitar under the whimsical pseudonym “Dr. Winston O’Boogie.” This collaboration breathed new, mid-seventies life into the 1967 classic.
Source:
https://www.youtube.com/watch?v=XagtuBIboPA
https://www.threads.com/@beliproduk.official/post/DWWNyeLEjD2