Final answer:
TCS food must be reheated to an internal temperature of at least 165°F for safety, checked with a calibrated food thermometer, before it can be served to guests. The correct answer is option A).
Step-by-step explanation:
When reheating a Time/Temperature Control for Safety (TCS) food from the cooler for immediate service to a guest, the food must be heated to an internal temperature of at least 165°F for 15 seconds, if it was cooked and refrigerated correctly. This temperature is sufficient to kill most types of bacteria and ensure the safety of the food.
To confirm that this temperature has been reached, it's advisable to use a food thermometer. Always make sure that the thermometer is properly calibrated, and that it's inserted into the thickest part of the food without touching any bones, which can skew the reading.
It's also important to remember that different types of food might have different reheating requirements, but the minimum standard of 165°F is a general rule for all TCS foods that are prepared, cooled, and reheated for hot holding. Please note that hot holding temperature should be maintained at 135°F or above after reheating.