I want to know the answer to the following question:
Along with Frank Sinatra, Doris Day, Johnny Mathis, Nat King Cole, and Perry Como, who was a prominent early adult contemporary radio artist?
All the background I'm provided with is that "Initially, the vocalists consisted of artists such as Frank Sinatra, Doris Day, Johnny Mathis, Connie Francis, Nat King Cole, Perry Como, and others.". Is that enough to answer the question?