How can food workers prevent allergic reactions in customers?

The correct answer emphasizes the importance of understanding and communicating the ingredients in food, which is critical for preventing allergic reactions in customers. Food allergies can result in severe health consequences, and many allergens can be hidden within common ingredients. By being knowledgeable about the ingredients in all dishes, food workers can appropriately respond to customer inquiries regarding allergies, ensuring that customers are informed about which dishes to avoid.

Properly labeling menu items also plays a vital role in this process. Clear and accurate labeling helps customers with food allergies make safe choices without having to guess or rely on their memory or the server's general knowledge. This proactive step significantly reduces the risk of accidental ingestion of allergens, ultimately safeguarding customer health and enhancing their dining experience.

The other options do not directly address the need for knowledge of ingredients or proper labeling, making them less effective for preventing allergic reactions.