The FDA Food Code identifies certain produce items as TCS (Time/Temperature Control for Safety) foods once they have been "processed" or cut.Diced tomatoesare specifically classified as a TCS food. While a whole tomato is shelf-stable, slicing or dicing it breaks the protective outer skin and allows pathogens that may have been on the surface to enter the nutrient-rich, moist interior. Tomatoes also have a neutral pH that supports the rapid growth of bacteria likeSalmonella. Therefore, they must be maintained and transported at$41^{\circ}F$ ($5^{\circ}C$) or lower.

Chopped celery (Option A) and sliced cucumbers (Option C) are currently not classified as TCS foods by the FDA, although they should still be handled with good hygiene and refrigerated for quality. Other plant foods that require $41^{\circ}F$ control include cut leafy greens, cut melons, and sprouts. When transporting diced tomatoes, the manager must use refrigerated trucks or insulated containers with ice packs to ensure the temperature does not rise into the Danger Zone. This is a critical point for salad bars and catering operations where pre-cut produce is common. Failure to maintain temperature control for cut tomatoes has been linked to numerous large-scale foodborne illness outbreaks.