Teacher says to the class "Tell me a word beginning with "A".

Of course Billy says "Ass".

He gets told off and the teacher then asks for a word beginning with "B".

Jenny says "Balls".

Again she gets told off. The teacher decides to leave out "C" for obvious reasons and asks for a word beginning with "D".

Johnny calls out "Dwarf".

The teacher congratulates him and asks what a Dwarf is.

Johnny replies "A short assed cunt with massive balls and a cock that touches the floor!"