Final answer:
The question addresses the frequency of inspections required for a cross-connection control program, which is typically annual to prevent water contamination.
Step-by-step explanation:
The subject of this question is the minimum requirements for a cross-connection control program, which pertains to health and safety standards in water supply systems. Cross-connection control programs are crucial to prevent contamination of clean water supplies through backflow or back siphoning from non-potable sources.
The correct frequency for inspections in such programs can vary depending on local regulations and standards, but usually, annual inspections are a common requirement. Regular inspections ensure that backflow prevention devices are working correctly and that no illegal or unsafe connections exist. Failing to perform these inspections can lead to water contamination incidents, posing serious health risks to the public.