Final answer:
The correct internal temperature to reheat TCS food for hot-holding in a microwave oven is 165°F (74°C) to safely kill harmful bacteria and prevent foodborne illnesses.
Step-by-step explanation:
When using a microwave oven for reheating Time/Temperature Control for Safety (TCS) food for hot-holding, the internal temperature of the food must reach 165°F (74°C). This temperature is considered safe for killing off potentially harmful bacteria and other pathogens that might be present in food items that are particularly susceptible to foodborne illness. It's crucial to ensure TCS foods, which include items like cooked meat, dairy products, and prepared fruits and vegetables, are reheated to this temperature to prevent foodborne diseases.