Final answer:
The lasagna must be reheated to a minimum internal temperature of 165°F (74°C) for hot holding to ensure food safety and prevent foodborne diseases.
Step-by-step explanation:
A food worker reheating a lasagna for hot holding must reheat to a minimum internal temperature of 165°F (74°C). This is in accordance with food safety guidelines to ensure that food reaches a high enough temperature to kill any potentially harmful bacteria. Specifically, for food safety and the prevention of foodborne illness, it is critical to heat foods past the danger zone temperatures where bacteria can thrive.
In the United States, the food industry typically uses the Fahrenheit scale to measure temperatures. Using a thermometer is the best way to ensure that the lasagna reaches the required safe internal temperature for hot holding.