Question: Which American singer-turned-entrepreneur released "Hits of the 50's", a cover album featuring renditions of classics by Cole, Avalon and Day?
Sentence (from "Testify to Love: The Very Best of Avalon"): Testify to Love: The Very Best of Avalon is Avalon's seventh release—the group's first greatest hits collection—and is titled appropriately after the quartet's hit, "Testify to Love".
Relevant evidence: No