Bud Light "Cut The Cheese"

This commercial contains a play on words relating to three expressions, listed below:

"To cut the cheese" is slang for "to fart"
"Who cut the cheese?"

"To pinch a loaf" is slang for "to defecate"
"He's in the bathroom pinching a loaf"
In standard English, a loaf is a shaped mass of baked bread.

"To pull one's finger" is slang used in the following way:
"A phrase used when playing a prank regarding flatulence, in which a mark is asked to pull the finger of the person playing the prank, who simultaneously flatulates so as to suggest a causal relationship between the pulling of the finger and the resulting expulsion of gas." (from allwords.com)