Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Which singer/songwriter, who began releasing hit singles in 1958, has had 3 albums (The Definitive Collection, Waking Up Is Hard to Do & The Music of My Life) on Billboard's Top 200 Albums chart between 2007 & 2010?
the definitive collection

What is the capital of the US state of Delaware?
delaware

Which singer has had hits with the groups, NERD, The Neptunes and Daft Punk as well as solo hits and accompanying Robin Thicke on 'Blurred Lines'?

blurred lines