I received Alton Brown's book: "I'm just here for the food" for my birthday.
As a funny add on, it has these refrigerator magnets of a cow, lamb, chicken, and pig, all with their tasty parts labeled.
Daughter wanted me to get those out and put them up, so we were looking at the book, which has a big chart of the animals and little arrows pointing out all the good stuff that comes from each one.
So daughter looks at the cow and see's all the steaks, roasts, ribs, etc., that are surrounding the cow and says: "Is that what the cow eats?"
Me, attempting at all costs to avoid the "no baby, we feed the cow, kill the cow, then eat the cow" conversation: "Um, no, mostly cows eat grass . . . do I hear your mom? Is she home from work?"
Daughter: "Oh! Maybe! Let me go see!"
Parenting 101: Only tell as much of the truth as you need to, to get out of the situation . . .