Final answer:
The most common food allergies reported by customers are dairy products and peanuts, which can cause reactions such as itching, swelling, and in severe cases anaphylaxis.
Step-by-step explanation:
The most common food allergies reported by customers are dairy products and peanuts. Food allergies occur when the immune system mistakenly identifies proteins found in food as threats, leading to a variety of symptoms such as itching, swelling of the lips and mouth, vomiting and diarrhea, and in severe cases anaphylaxis. Foods that frequently cause allergic reactions include nuts, eggs, grains, and milk, with peanuts being a particularly common allergen that can provoke severe reactions in sensitive individuals.
Therefore, the correct answer is b) Dairy products and peanuts, which are among the eight most common food allergens. These allergens are responsible for a significant proportion of food allergy reactions in restaurants and other food service establishments.