It’s from these:
Antiques Roadshow
Kathy Griffin: My Life on the D-List
Jamie Oliver’s Food Revolution
Dirty Jobs
MythBusters
Undercover Boss
I would split my vote between Dirty Jobs and Mythbusters.
I wanted to do a poll, but I don’t know how. 
How is Mythbusters a reality show
I guess I, too, am a little unclear on what a “reality show” is. I would never have thought Mythbusters or Dirty Jobs were reality shows.
I think the shows you mention are more properly called ‘documentaries’.
That said…“and the Emmy goes to…MIKE ROWE, DIRTY JOBS, yay!”
Anything that’s unscripted might be considered a “reality” show. TWOP has three reality categories – Competitive (Idol, the Dance shows, Apprentice, Design Star, etc.), Candid (the Real Housewives franchise, Bridezillas), and How-To (Holmes on Homes, This Old House, the decorating shows).
Hmmm. That doesn’t help classify Dirty Jobs and Mythbusters. Candid, maybe?
When I think “documentary”, I think historical, educational, cultural, biographical.
Anyhoo, I’d vote for Dirty Jobs.