This classic trick question asks which sentence is correct: “The yolk of an egg is white” or “The yolk of an egg are white”?
The answer is: neither sentence is correct.
The grammar is not the real trick. An egg yolk is usually yellow or orange, not white. The white part of an egg is called the egg white, while the yolk is the colored center.
Many people focus so much on deciding between “is” and “are” that they miss the factual mistake hidden in both choices. Grammatically, “the yolk” is singular and would take “is,” but the statement “the yolk is white” is still false.
That makes this a good example of a riddle where the obvious grammar question distracts you from the real clue.


