1. Lead singer of the Doobie Brothers on such songs as "What a Fool Believes" and "One Step Closer": Michael McDonald
2. John's songwriting partner: Paul McCartney
3. He taught us how to do "The Hustle" in 1975: Van McCoy
4. Canadian singer whose hits include "Angel" and "Building a Mystery": Sarah McLachlan
5. Two-fifths of the most successful Fleetwood Mac lineup: John and Christine McVie
6. And on this farm, he had some chicks, e-i-e-i-o: "Old McDonald Had A Farm"
7. "Don't worry...be happy...": Bobby McFerrin
8. Faith Hill's husband: Tim McGraw
9. His "Rock Your Baby" was the first Number One hit for KC of the Sunshine Band: George McCrae
10. DMC: Darryl McDaniels
11. He wrote "Drinkin' Wine, Spo-Dee-O-Dee": Stick McGhee
12.He recorded as Pigpen, but his real name was...: Ronald McKernan
13.He recorded a song about truckers named Pigpen, Rubber Duck, and Sodbuster: C.W. McCall
14. Deep-voiced country singer who won Season 10 of American Idol: Scotty McCreary
15. Prince's boss in "Raspberry Beret": Mr. McGee
16. Female lead singer of the Fifth Dimension who later hosted Solid Gold: Marilyn McCoo
17. If you're going to San Francisco, he told you to be sure to wear some flowers in your hair: Scott McKenzie

Bonus: The lead singer of the Bay City Rollers in the mid-70s: Leslie McKeown