Which of the following methods can prevent foodborne illnesses most effectively?

Washing hands frequently is one of the most effective methods to prevent foodborne illnesses because proper hand hygiene directly removes harmful pathogens that can be transferred to food. When food handlers wash their hands with soap and water at critical times, such as before preparing or eating food, after using the restroom, or after handling raw meat, they significantly reduce the risk of contaminating food with bacteria, viruses, and other pathogens. This is essential in maintaining a safe food environment.

Other methods listed do not contribute effectively to food safety. For instance, storing food at room temperature can promote the growth of pathogens; relying on smell can lead to consuming spoiled or contaminated food; and using open containers can expose food to airborne pathogens or pests. Proper handwashing remains a fundamental practice in food safety that directly impacts the likelihood of foodborne illnesses.