The following statement is given, “It’s not true there are substitutes for anything. If you want omelets, you need eggs. There are no substitutes for eggs in an omelet.” Analyze this argument critically and use the relevant economic concept(s) to justify your answer.

The answer given in the book isn't very clear to me, as the answer is supposed to involve the inegration of the concepts related to elasticity and the concept of demand: The substitutes for eggs in this case would include all the substitutes for omelettes (no one needs an omelette), as well as all the ingredients that complement eggs in an omelette and that can also be used as partial substitutes for eggs, such as cheese, potatoes, peppers, ham, or onions.