What type of food should be kept in the refrigerator for safety after being opened?

When considering food safety after being opened, UHT milk is the correct choice to keep in the refrigerator. UHT (Ultra-High Temperature) milk undergoes a process that extends its shelf life, allowing it to be stored at room temperature until opened. However, once opened, it is sensitive to spoilage and should be refrigerated to prevent the growth of bacteria. Keeping opened UHT milk in the refrigerator helps ensure it remains safe to consume for a longer period.

The other options, while they may have extended shelf lives, do not necessitate refrigeration after opening for food safety. Soy sauce, for instance, can be stored at room temperature due to its high salt content, which acts as a preservative. Similarly, pickles and honey can also be kept out of the refrigerator after opening because their acidic or sugar-based nature helps inhibit bacterial growth.