Which of these fictional bands is playing during the dance off scene in the 1978 Hollywood film "Grease"?

"Grease" is a 1978 American musical romantic comedy film based on the 1971 musical of the same name. The film depicts the lives of greaser Danny Zuko (John Travolta) and Australian transfer student Sandy Olsson (Olivia Newton-John) who develop an attraction for each other. Released in June 1978, Grease was successful both critically and commercially, becoming the highest-grossing musical film ever at the time.

In one of the film's more memorable scenes, "Johnny Casino and The Gamblers" is the musical group performing at Rydell High School's National Dance-Off. They were portrayed by the real-life performing group Sha Na Na. Sha Na Na's tracks on the film and Grease soundtrack include "Those Magic Changes" and "Born to Hand Jive"; as well as cover songs from the early rock and roll era: "Hound Dog", "Blue Moon", "Tears on My Pillow", and "Rock & Roll Is Here to Stay."