A Riddle

All credit goes to L, the Admin of the L (Death Note) page.

Colin, my friend! On my Quest I met a man. None of you will be able to solve my riddle, he said. George tried to solve it and thought the answer was "Milk". Robert tried to solve it and thought the answer was "Cheese". Although we tried hard none of us was able to solve the riddle. To you it might seem easy but believe me it's not. Unlike so many other riddles there are, he said, this one has only one answer. Yoghurt, Steak and even Cattle, I swear we guessed it all. Albert tried even his own name as an answer. There we were, totally stumped. I had no idea what to say anymore, I thought I was smart. On a scale of one to ten he said, this riddle was 1. None of you will be able to solve my riddle, he said. See if any can solve if you repeat what I told you, he said, as it is impossible to solve this riddle if you get even a single fact wrong.

This is the whole riddle.