Final answer:
Casseroles being reheated must reach an internal temperature of 165 degrees Fahrenheit according to USDA guidelines to be safe for consumption, which corresponds to answer option D.
Step-by-step explanation:
Casseroles that are being reheated must reach a minimal internal temperature to ensure that any potential bacteria are killed and the food is safe to eat. The United States Department of Agriculture (USDA) guidelines indicate that a safe internal temperature for reheated dishes like casseroles is 165°F. This temperature is effective at killing bacteria and making leftovers safe for consumption.
It is crucial to use a food thermometer to check the internal temperature of the food to be sure it has reached this safe temperature. Foods kept in the danger zone between 40°F and 140°F for more than two hours should be discarded to prevent the likelihood of foodborne illness.
Therefore, the answer to the question is D. 165 degrees Fahrenheit as the minimal internal temperature that a reheated casserole must reach.