Two Scottish nuns travel to the U.S. One nun tells the other, “You know, in America they eat dogs.”
They land in New York and take a cab into Manhattan. Later that day, they take a walk. The nuns see a hot dog stand and order two hot dogs. The first nun takes hers out of its wrapping, looks at it, and asks the other nun, “What part did you get?”
Source: Adapted from Carroll, Noel. Humour: A Very Short Introduction. Oxford, UK: Oxford University Press, 2014.