Final answer:
To serve raw or undercooked foods in a restaurant, one would need to obtain a variance from the regulatory authority to ensure compliance with food safety standards.
Step-by-step explanation:
The requirement to obtain a variance from a regulatory authority typically depends on the nature of the change being proposed to a business's operations. In the context of a restaurant, a variance would likely be needed if one is planning to serve raw or undercooked foods, which is option D. This is because serving such foods introduces a different level of risk to public health that may not be covered under the existing health and safety permits of the establishment. Regulatory authorities require variances to ensure that all food service operations comply with established food safety guidelines. This compliance could involve demonstrating that the restaurant has appropriate plans and procedures in place to handle, store, and serve these foods safely to prevent foodborne illnesses. Changes such as altering the menu, installing new kitchen equipment, or modifying interior decor typically do not require a variance unless they impact the structural or sanitation standards as defined by health code regulations.