When are you required to immediately close and stop serving food?

The requirement to immediately close and stop serving food is tied specifically to situations that can pose a significant risk to food safety. Not having water, hot water, electricity, or experiencing a sewage backup means that essential services necessary for safe food preparation and handling are compromised. Without water, food cannot be properly washed, cooked, or served safely; hot water is crucial for cleaning and sanitizing dishes and utensils. A lack of electricity can prevent refrigeration of perishable items, which could lead to foodborne illnesses. A sewage backup presents a severe health hazard, as it can contaminate food and food preparation areas.

In contrast, a broken stove, while it does affect cooking capabilities, does not necessarily compromise overall food safety to the extent that a lack of essential utilities does. Similarly, a customer complaint, while it should be taken seriously, does not inherently indicate a food safety issue that warrants immediate closure. Lastly, while a malfunctioning refrigerator is concerning, it may not require immediate closure unless it leads to an unsafe storage situation that cannot be remedied promptly. Thus, the scenario that leads to a direct threat to public health and safety is the lack of essential services listed in the correct choice.