What is the proper way to handle leftovers?

Storing leftovers in a refrigerator is the proper way to handle them because it helps to inhibit the growth of bacteria and other pathogens that can lead to foodborne illnesses. When leftovers are placed in a refrigerator set at 40°F (4°C) or below, it slows down microbial activity, keeping the food safe for consumption for a longer period.

Refrigeration also helps maintain the quality and flavor of the food, preventing spoilage. Leftovers should ideally be consumed within a few days when stored in the refrigerator, so it's important to manage time and temperature effectively to ensure safety.

Keeping food at room temperature, as suggested in one of the other options, can lead to rapid bacterial growth, significantly increasing the risk of foodborne illness. Similarly, freezing leftovers without wrapping them can lead to freezer burn and loss of quality, while reheating food without cleaning dishes can introduce contaminants into the food, potentially leading to food safety hazards. Thus, proper refrigeration stands out as the best practice.