It is now common for people to identify as gluten intolerant. In ancient societies, it was common for people to identify as poultry intolerant. This eventually ended when people realized they were misdiagnosing poultry intolerance with food poisoning caused by mistakes in the birds' preparation. Eventually, people will realize that they are not actually gluten sensitive. The reference to the ancient civilization's poultry intolerance plays which of the following roles in the argument? ['Serves as a historical example of food intolerance.', "Ties the argument's reasoning together.", 'Provides an example of how societies can misdiagnose food intolerance.', "Distracts the reader from the argument's primary purpose."]